lg math grade 5 - ratl.nos.percent v2.0

7/28/2019 LG MATH Grade 5 - Ratl.nos.Percent v2.0

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Lesson Guide

In

Elementary MathematicsGrade 5

Reformatted for distribution via

DepEd LEARNING RESOURCE MANAGEMENT and DEVELOPMENT SYSTEM PORTAL

DEPARTMENT OF EDUCATIONBUREAU OF ELEMENTARY EDUCATION

in coordination with

ATENEO DE MANILA UNIVERSITY

2010

Chapter II

Rational Numbers

Percent

INSTRUCTIONAL MATERIALS COUNCIL SECRETARIAT, 2011


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Lesson Guides in Elementary MathematicsGrade 5

Copyright 2003All rights reserved. No part of these lesson guides shall be reproduced in any form without a writtenpermission from the Bureau of Elementary Education, Department of Education.

The Mathematics Writing Committee

GRADE 5

Region 3

Nelia D. Bamba PampangaMagdalena P. Garcia Angeles City

Region 4-A (CALABARZON)

Gundalina C. Gonzales Batangas

Gerlie Ilagan QuezonConsuelo Caringal Batangas

National Capital Region (NCR)

Teresita P. Tagulao Pasig CityAlyn G. Mendoza Mandaluyong CityEmma S. Makasiray Pasig/San JuanEster A. Santiago ValenzuelaMilagros Juakay Pasig/San JuanLucia Almazan ManilaJulie La Guardia Valenzuela

Bureau of Elementary Education (BEE)

Federico L. ReynoNoemi B. Aguilar

Ateneo de Manila University

Grace Uy

Support Staff

Ferdinand S. BergadoMa. Cristina C. Capellan

Emilene Judith S. SisonJulius Peter M. SamuldeRoy L. ConcepcionMarcelino C. BatallerMyrna D. LatozaEric S. de Guia Illustrator

Consultants

Fr. Bienvenido F. Nebres, SJ President,Ateneo de Manila University

Carmela C. Oracion Principal,Ateneo de Manila University

Pacita E. HosakaAteneo de Manila University

Project Management

Yolanda S. Quijano Director IVAngelita M. Esdicul Director III

Simeona T. Ebol Chief, Curriculum Development DivisionIrene C. De Robles OIC, Asst. Chief, Curriculum Development Division

Virginia T. Fernandez Project Coordinator

EXECUTIVE COMMITTEE

Jesli A. Lapus Secretary, Department of EducationJesus G. Galvan OIC, Undersecretary for Finance and Administration

Vilma L. Labrador Undersecretary for Programs and ProjectsTeresita G. Inciong Assistant Secretary for Programs and Projects

Printed By:

ISBN 971-92775-4-8


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TABLE OF CONTENTS

Introduction .................................................................................................................................. ivMatrix ........................................................................................................................................ v

II. RATIONAL NUMBERS

Percent

Visualizing Percent ............................................................................................................... 1Relationship between Fractions, Ratio and Percent ............................................................ 5Relationship between Percent and Decimal ......................................................................... 9Relating Fractions, Ratios, Decimals and Percents ............................................................. 13Meaning of Elements used in Solving Percentage Problems .............................................. 18Determining the Percentage of a Number ............................................................................ 24


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I N T R O D U C T I O N

The Lesson Guides in Elementary Mathematics were developed by the

Department of Education through the Bureau of Elementary Education in

coordination with the Ateneo de Manila University. These resource materials

have been purposely prepared to help improve the mathematics instruction in

the elementary grades. These provide integration of values and life skills using

different teaching strategies for an interactive teaching/learning process.

Multiple intelligences techniques like games, puzzles, songs, etc. are also

integrated in each lesson; hence, learning Mathematics becomes fun and

enjoyable. Furthermore, Higher Order Thinking Skills (HOTS) activities are

incorporated in the lessons.

The skills are consistent with the Basic Education Curriculum

(BEC)/Philippine Elementary Learning Competencies (PELC). These should be

used by the teachers as a guide in their day-to-day teaching plans.


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MATRIX IN ELEMENTARY MATHEMATICSGrade V

COMPETENCIES VALUES INTEGRATED STRATEGIES USEDMULTIPLE INTELLIGENCES

TECHNIQUESWith HOTS

II. RATIONAL NUMBERS

Comprehension of Percent

1. Relate fractions/ratios, decimals andpercent

1.1 Visualize the meaning of percent(%)

Cooperation,Appreciation for the

use of percent inreal-life situations

Modeling, Drawingpictures, Concept

development

Drawing, Hands-onactivities, Manipulative,

Cooperative groups

1.2 Give the relationship

between fractions/ratios andpercents (with visual models)

Healthconsciousness,

Showing concernsfor others

Conceptdevelopment,

Modeling, Makingtables

Collecting data, Scientificmethod, Music, Dancing,Body movements, Using

chart

between percent and decimal(with visual models)

Cooperation Conceptdevelopment, Acting

out the problem

Reading, Writing,Speaking, Manipulative

among fractions/ ratios, decimalsand percents

Honesty Acting out theproblem, Modeling,Preparing a table

Skit and play, Hands-onactivities, Reading,Writing, Speaking,

Drawing


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Visualizing Percent

I. Learning Objectives

Cognitive: Visualize the meaning of percentName the percent illustrated by shaded region

Psychomotor: Shade the percent, fraction or decimal givenAffective: Work cooperatively with groupmates

To appreciate the use of percent in real-life situations

II. Learning Content

Skill: Visualizing percentReference: BEC-PELC II.J.1.1Materials: 10 x 10 guides, acetate, grid books, geoboard, graphing paper, crayons,

signs or posters or advertisement or newspaper cutouts with percentValue: Cooperation, appreciation for use of percent in real-life situations

III. Learning Experiences

A. Preparatory Activities

1. Mental Math

Multiplying and dividing by multiples of 10 and 5

Strategy: Pinball Wizard

Materials: 4 pinball machine for each group,paper for recording score

Mechanics:a. Divide class into groups of 4. Provide each group with copy of the pinball machine.

b. Beginning at start, travel along paths in any direction, doing the Math mentally as yougo.c. The goal is to find route/path that gives the highest score.d. Record the score of each member of the team.e. Teacher may vary the game by asking each group to come up with a path. The team

that will produce the highest number wins.

2. Review

Review previous lesson.Give 1-2 examples.

B. Developmental Activities

1. Presentation

a. Ask pupils where they encounter percent.b. Show pupils advertisements, posters, pictures or cutouts showing use of percent.

Ask what they mean.


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c. Show also misleading drawing like.

T-shirt made of50% cotton50% polyester

Strategy 1: Using model of shaded region

Materials: crayons, grid 10 x 10, grid board or acetate with number pens, colored chalk

a. Teacher defines percent as per hundred or for every hundred. It comes from theLatin words per and centum. The symbol used is %.

b. Teacher shows 10 x 10 grid. Ask pupils how many 1 x 1 squares are in the grid(100).

c. Teacher shades 5 1 x 1 squares. Ask pupils what percent is shaded. (5%)Show 10 squares shaded; 50 squares; 100 squares. Elicit the correct percent

shaded.d. Teacher then shows 150 squares shaded and then ask what percent is shaded.

e. Give more examples.f. Reverse roles. Teacher gives percent and let pupils shade the corresponding region

in the grid.

Strategy 2: Geoboard

a. Give geoboard by group.b. Let them do the following;

a) get a rubber band and enclose the 100 squaresb) get another rubber band (red) and enclose 40 squaresc) get yellow rubber band and enclose 75 squares etc.

c. Teacher defines percent as per hundred. The symbol is (%) percent.d. If the 10 x 10 squares enclosed is considered 1 whole, the 40 squares enclosed by

red rubber band is 40%. Ask pupils what % is represented by the squares enclosedby yellow rubber band?

e. Have pupils show 5% using the geoboards. Check answers.f. Give more examples.

Strategy 3: Geoboard

a. Drawing, cutouts or real leaves. Big - 28, medium 30, small 42. How manyleaves are small? Medium? Big? What percent of the leaves are small? Medium?Big?

GreatestSale ever100% off


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b. Drawing or cutouts of 10 red balls; 22 yellow balls; 16 green ball; 36 blue balls and16 orange balls. How many balls are there in all? What percent of the balls are red?yellow? blue? orange? green?

2. Fixing Skills

Study the 100-chart.

1 2 3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30

31 32 33 34 35 36 37 38 39 40

41 42 43 44 45 46 47 48 49 50

51 52 53 54 55 56 57 58 59 60

61 62 63 64 65 66 67 68 69 70

71 72 73 74 75 76 77 78 79 80

81 82 83 84 85 86 87 88 89 90

91 92 93 94 95 96 97 98 99 100

A. Give the answer of the following questions.

1. How many counting numbers are there? What percent shows the 100 numbersfrom the chart?

2. What part of the chart are even numbers? /odd What percent of it from thechart?

3. How many percent are the following?

a. multiples of 10? 5? 3?b. prime numbersc. composite numbers?

B. Give the number of units for the following.

1. 6% =2. 64% =3. 75% =4. 103% =5. 534% =

3. Generalization

What is the meaning of percent? What is the symbol for percent?

A percent is a ratio whose denominator is 100. Percent is another way of sayinghundredth or in a hundred. The symbol is % is read as percent.


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C. Application

Using Hundred Charts

Show the following by drawing:

1) 25%

2) 16%3) 40%

Drawing or cutouts of 15 buko, 28 pineapples, 24 apples, 10 watermelons, 23 mangoes.

1. How many fruits are there in all?2. What percent of the fruits are pineapples?3. What percent of the fruits are apples?4. What percent of the fruits are buko?5. What percent of the fruits are mangoes?

IV. Evaluation

A. Drawing or 100 squares with different colors: 10 yellow, 36 green, 23 blue, 15 pink, 16 red.Answer the following questions:

1. 15% is represented by (red, pink, green, blue)2. 10% is represented by (blue, red, pink, yellow)3. 23% is represented by (green, blue, pink, yellow)4. Green is (10%, 36%, 15%, 16%)5. Red is (23%, 10%, 15%, 16%)

B. Drawing or 100 squares wherein 42 squares are shaded. (Figure I)Drawing or 100 squares wherein 63 squares are shaded. (Figure II)

1. How many small squares are there in Figure I?


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2. What percent is shaded in Figure I?3. How many squares are there in Figure II?4. What percent is not shaded in Figure I?5. What percent is not shaded in Figure II?

V. Assignment

A. Clip advertisement from magazine/newspapers that shows use of percent.B. Show the following by drawing:

1) 10%2) 45%3) 71%4) 60%5) 85%

Relationship between Fractions, Ratios and Percent


Cognitive: Give the relationship between fractions/ratios and decimal (with visualmodels)

Psychomotor: Show relationship between fractions/ratios and percentsAffective: Show concern for others


Skill: Giving the relationship between fractions/ratios and percents(with visual models)

Reference: BEC-PELC II.J.1.2.aMaterials: Cassette player, real objects inside the room

Value: Health consciousness



1. Review

Review meaning of percent

Strategy: Relay Game

Materials: cardboard strips representing 10s and 1sMechanics:

a. Divide children into 4 groups.b. Cardboard strips representing 10s and 1s will be distributed to the four groups.c. The teacher gives a problem and the pupil from each group hurriedly answers the

questions using the cardboard strips like (85% of the plants were watered. Howmany percent were not watered?) Pupils having the strips with 10 division and 5 onedivision each to represent 15% as the answer will go in front to show the answer.

d. The group that answers first correctly gets the point.e. Game continues until all the participants have participated.f. The group with the most points wins the game.

Using a reference grid explain further the meaning of percent.


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Reference Grid

75%

Thus, 75% can be shown by shading 75 squares.

2. Motivation

Who among you have baby brothers and sisters who still take milk from bottles? Do youknow how to prepare their milk? How many ounces of water do you use? How manyscoops of milk do you put?(Pupils may say for every 4 ounces of water they put 2 scoops of milk before shaking thebottle.)


1. Presentation

Strategy 1: Survival Game (Concept Development)

Materials: Cassette tape (Modeling)Mechanics:a. Let 5 boys and 5 girls stand in front of the class forming a circle. While the music is

being played the participants move around.b. When the music stops the teacher will say The boat is sinking, all aboard by 2. The

participants then group themselves by 2.c. The group continues till the players form a ratio.

Discuss the following to the pupils:

For instance, in the first group there are 1 girls and 4 boys left. Then the ratio of boys togirls is 4:1.

The ratio of girls to boys is 1:4.

If we are to write the ratio 1:4 in fraction, which will be the numerator? the denominator?If we are to get how many percent of the pupils are girls, in relation to the group, dividethe numerator by the denominator.

.254 1.00

820

The girls are 25% in relation to the boys in the group.

Strategy 2: Collecting Data (Making Tables)

Let the pupils interview 100 pupils in the school campus about their favorite TV shows.Then write fractions, decimals and percent gathered from the data.


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Student Data

Category No. of Pupils Ratio Fraction Decimal

TV Patrol 18 0.18

24 Oras 16 0.16

Starstruck 28 0.28

Woowawie 15 0.15

Eat Bulaga 20 0.20

Mel & Joey 3 0.03

Fraction Decimal

a.

b.

c.

d.e.

After completing the data the discussion follows. What is the relationship of ratios tofraction? to percent?If your data is written in the ratio form, can you write it in fraction form? How can we getpercent equivalent of a ratio and a fraction?

Strategy 3: Changing Fraction to Higher Form with 100 as Denominator

Examples:

a.

4

3 =

4

3 x

25

25=

100

75= 0.75

a.5

4 =

5

4 x

20

20 =

100

80= 0.80

b.4

7 =

4

7 x

25

25 =

100

75= 1.75

Observe some examples.

What happen to the given fractions?

What kind of fractions multiplied to the given fractions?

What do you notice to their denominators?

Do the value the same? Why? How did the fractions changed to decimals?


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2. Fixing Skills

A. Express each shaded as a ratio and as decimal of the whole figure.

1. 2.

3.

B. Write each fraction as decimal.

1.100

65 = _____ 4.

25

24= _____

2.5024 = _____ 5.

52 = _____

3.20

3= _____

3. Generalization

Ratio is a comparison between two or more quantities. It can also be expressed as afraction the first number is the numerator while the second number is the denominator.Through ratios and fractions we can get the decimalrs equivalent by dividing thenumerator by the denominator or changing the fraction to higher terms with 100 as

denominator.

C. Application

Solve each problem.

1. Seventy-five of every 100 people a newspaper daily. What is the fractional part? How itis written to decimal number?

Ratio: _____Decimal: _____




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IV. Evaluation

Use the chart below to name each ratio, fraction and decimal.

1. J. Rizals Team Ratio Fraction Decimal

wins to loses

loses to wins

wins to games played

loses to games played

2. M.L. Quezons Team

wins to loses loses to wins

wins to games played

loses to games played

V. Assignment

Complete the table below using the given data.

1. The set of even numbers from 1 to 20.2. The set of odd numbers from 1 to 20.3. The set of composite numbers from 1 to 20.4. The set of prime numbers from 1 to 20.

Relationship between Percent and Decimal


Cognitive: Give the relationship between decimal and percent (with visual models)Psychomotor: Change percent to decimal or vice versaAffective: Manifest cooperation among members of the group


Skill: Giving the relationship between percent and decimalReference: BEC-PELC II.J.1.2.bMaterials: Geoboard, rubber band

District Chess Tournament

Team Games Played Wins Loses

Jose Rizal 10 6 4

M.L. Quezon 10 7 3

P. Burgos 10 5 5

Lakandula 10 8 2

Ratio Fraction Decimal


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Value: Cooperation



1. Mental Computation

Give the ratio of girls to boys inside the classroom. If the girls doubled and the boys ratioincreased by 8, what is the ratio of girls to boys?

2. Review

Changing fractions to decimals or vice versa

Strategy: Relay

a. Pupils will change fractions to decimals or vice versa

b. Ask questions:

1) How will you change fractions to decimals with denominators of 10, 100, 1,000 todecimals?

2) How will you change common fractions like4

3,

2

1,

5

3 , etc. to decimals?

3) How will you change decimals to fractions?


1. Presentation

Strategy 1: Manipulative Geo Board

a. Use rubber band in your geoboard with 100 equal units to show the number ofsquares to be enclosed for the given decimal number.

Example:100

85,100

35,100

3,100

5

Fractions Decimals

10

7

5

3

5

3

4

3

2

1


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How will you write in decimals? How many decimal places are there for hundredths?Complete the table:

b. If the decimal number is in the tenths, what will you add to make it hundredths?Example: 0.5 0.7 0.3

Show in your geoboard using rubber band. What percent is it?Complete the table:0.5 = 0.50 = 50%

0.3 = 0.30 = 30%0.7 = 0.70 = 70%

Strategy 2: Problem Opener

a. The school garden is about 25% of the total land area of the school. How will youwrite 25% in decimals?

Percent Fraction Decimal25%

100

25

0.25

b. Of the 100 mangoes 30% are still unripe. What part of the mangoes are unripe?

What part of it are ripe?

c. Give more examples.

2. Fixing Skills

A. Write each fraction to percent.

1.100

38 = _____ 4.

50

28= _____

2.50

46= _____ 5.

25

73 = _____

Fraction Decimals Percent

100

85 0.85 85%

100

25

0.25 25%

100

3 0.03 3%

100

5 0.05 5%

Percent Fraction DecimalUnripe 30%

10

3

100

30

0.3

Ripe 70%

10

7

100

70

0.7


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3.5

2 = _____

B. Write as decimal number.

1. 25% = _____ 4. 56% = _____

2. 68% = _____ 5. 135% = _____

3. 19% = _____

C. Write each decimal to percent.

1. 0.48 = _____ 4. 0.88 = _____

2. 0.63 = _____ 5. 4.05 = _____

3. 0.88 = _____

3. Generalization

How will you change percent to decimals?

To change a percent to decimal, think of the percent as a fraction with a denominatorof 100. Write the fraction as 2 place decimals or hundredths or simply move the decimalpoint 2 places to the left and drop the % sign.

How will you change decimals to percent?

To change decimals to percent, think of the decimal as a fraction with a denominatorof 100. Then write the fraction as a percent or simply move the decimal point 2 places tothe right, then affix the % sign.

C. Application

A. Change to decimal.

1) 86% = ______ 2) 17% = ______3) 32% = ______ 4) 9% = ______5) 5% = ______

B. Change to percent.

1) 0.04 = ______2) 1.2 = ______3) 0.6 = ______4) 0.41 = ______5) 0.7 = ______


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C. Solve.

Out of the 50 students surveyed, 21 prefer cheese pizza, 11 prefer Hawaiian pizza,and the rest want pepperoni pizza. What percent of the students prefer1. cheese pizza ______2. hawaiian pizza ______3. pepperoni pizza ______4. cheese and Hawaiian ______5. pepperoni and hawaiian _____

Write the decimal value of each percent.

IV. Evaluation

A. Write each as a decimal.1) 45% 2) 21% 3) 8%4) 39% 5) 90%

B. Write each as a percent.1) 0.17 2) 0.02 3) 0.6

4) 0.70 5) 0.12

C. Compare, use >, < or =.1) 0.50 50%3) 0.2 2%5) 23% 0.023

2) 78% 0.784) 9% 0.09

D. Read and answer:1) The school building occupies 65% of the schools land area. Express 65% as a decimal.

____2) In a Grade IV class 20% are boys while in grade V class, 0.2 are boys. How does 20%

compare with 0.2? ___3) 90% out of 100 guavas were sold. How will you write 90% in decimals?

4) 5% out of 100 workers were absent? Write 5% in decimals.5) Nora got 80% of a 50-item test. How will you write the 80% in decimals?

V. Assignment

Write answer briefly.1) 15% of the class of Miss Ramos are absent. Write 15% in decimals.2) How do you write 6.5 to percent?3) Compare 0.9 and 9% by converting each to the other.4) 27 % of the fruits are ripe. How do you write 27% in decimals?5) Construct your own mathematical situation.

Relating Fractions/Ratios, Decimals and Percent


Cognitive: Give the relationship between fractions/ratios, decimals and percent (withvisual models)

Psychomotor: Change fractions to decimals and percent or vise versaAffective: Manifest honest and wise choice of food


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Skill: Giving the relationship between fractions/ratios, decimals and percentReference: BEC-PELC II.J.1.2.cMaterials: fruits, vegetables, grid, colored crayonsValue: Honesty



1. Mental Problem

There are 550 chairs in the hall. Two hundred forty-six are occupied. How manychairs are vacant? What is the ratio of the number of chairs occupied to vacant chairs?What is the ratio of occupied chairs to the total number of chairs?

2. Drill

Changing fractions to decimals

Strategy1: Matching Game

Each group will match the fraction with denominator of 10, 100 and their equivalent indecimals.

COLUMN A COLUMN B

100

7

0.15

100

15

0.75

100

75

0.07

10

4

0.8

10

8

0.4

0.9


1. Presentation

Strategy 1: Market Day

a. Teachers table will be the market with plenty of fruits and vegetables.b. Each group will be given a basket. They will buy/get a total of 50 fruits and 50

vegetables of different kinds.c. Each group will report (post in chart or manila paper) the fractional part of each kind

of fruit or vegetables they have in their basket.Note: Compare using part and part to whole.


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Example: We are happy to report that our group have in our basket a total of 50fruits and 50 vegetables or 100 pieces in all.

10

3 of the 50 fruits or 15 pieces are mangoes or100

15 .

10

1 of the 50 fruits or 5 pieces are mangoes or

100

5 .

5

3of the 50 fruits or 30 pieces are mangoes or

100

30 .

10

1 of the 50 vegetables or 5 pieces are eggplant =100

5.

25

1 of the 50 vegetables or 2 pieces are upo or100

2 .

5

1of the 50 vegetables or 10 pieces are carrots or

100

10.

25

4of the 50 vegetables or 8 pieces are carrots or

100

8.

5

2of the 50 vegetables or 20 pieces are beans or

100

20 .

10

1 of the 50 vegetables or 5 pieces are pechay or100

5 .

d. Complete the table by changing the given fractions to decimals to percent.

Ratios/Fractions Decimals Percent

10

3 =100

30

100

5

100

2

e. Ask the following questions:f. What is the other way of changing common fraction to decimals?

Divide the numerator by the denominator

e.g.5

1=

2.0

10

105 etc.

g. How will you change decimal to percent?Move the decimal point 2 places to the right 0.2 = 20%

h. Another way of changing fraction to decimal.

5

1 x20

20 =100

20= 0.20 = 20%

Strategy 2: Visualization using Grid (Modeling)

Pupils will be given grid per group. Use color to show the following then complete thechart.


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Color Number of Squares Fraction Decimal Percent

Red 6 out of 100

Blue 35 out of 100

Green 20 out of 100

Yellow 9 out of 100

Pink 30 out of 100

Pupils per group will report their answer. Give more exercises.

2. Fixing Skills

A. Write each as a percent.

1. 0.6 = _____ 4. 1.2 = ______2. 0.39 = _____ 5. 2.268 = _____3. 0.061 = _____

B. Write each as a decimal.

1. 38% = _____ 4. 213% = ______2. 87.5% = _____ 5. 0.98% = _____3. 105% = _____

C. Use >,


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C. Application

1. Change the following fractions to decimals and then to percent.

Decimal Percent

1)

3

2= ______ ______

2)8

1= ______ ______

3)5

3= ______ ______

2. Change to decimals and then to fractions.

Decimal Fraction1) 60% = ______ _______2) 70% = ______ _______

3. Solve each problem.

1. 75 percent of the class are girls. Express 75% as a decimal.

2. There were 250 cookies shared by Rene, Jona, and Phiel. Rene got of the cookies

and the rest were shared between Jona and Phiel in the ratio 2:3. How manycookies did Rene, Jona and Phiel get?

IV. Evaluation

A. Complete the chart.

Fraction Decimal Percent

100

13

0.04

90%

35%

5

4

B. Change the given fraction to decimal and to percent.

Decimal Percent1)

2

1

2)

6

4

3)

4

3


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C. Change the given percent to decimal and fraction in the lowest terms.

D. Changing decimal to percent and to fraction in the lowest terms.

V. Assignment

Change each number in percent to a fraction in its simplest form and then to decimal.

Fraction Decimal1) 66% _________ _________

2) 75% _________ _________3) 90% _________ _________4) 15% _________ _________5) 60% _________ _________6) 120% _________ _________7) 100% _________ _________8) 180% _________ _________9) 200% _________ _________10) 80% _________ _________

Meaning of the Elements used in Solving Percentage Problems


Cognitive: Give the meaning of the elements used in solving percentage problems suchas percentage, rate and base

Psychomotor: Write the meaning of percentage, rate and baseAffective: Choose nutritious food to maintain health

Cooperate with group members


Skill: Giving the meaning of percentage, rate and baseReference: BEC-PELC II.J.1.3

Materials: Hundred grid cardboards, crayons, fraction stripsValue: Proper choice of food, cooperation, alertness



1. Drill

Drill on Percent

Decimal Fraction1) 85%

2) 12%

3) 70%

Percent Fraction1) 0.26

2) 0.8

3) 0.95


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Strategy 1: Parade of Colors (Modeling)

Materials: 5 pieces of hundred square grid cardboard and crayonsMechanics:a. Divide the class into 5 groups.b. Distribute cardboards, one for each group.c. Let pupils shade different portions with different colors. Example: green 12%,

yellow 25%, blue 20%, red 35%, indicate the % for the unshaded part.d. The first group to present work accurately done wins the game.

Strategy 2: Making Predictions (Guess and check)

Situation:Father owns a vegetable farm. Let us make intelligent guesses on the portion of the farm(in percent form) planted with different kinds of vegetables.Materials: 5 pieces of hundred square grid board.Mechanics:a. Divide the class into 5 groups.b. Before the activity, ask each group to make predictions on the percentage of areas

planted with different kinds of vegetables in Fathers farm.

c. Provide each group with hundred grid board which look like this:

d. Open the cardboard and make a record of actual data.

e. Make a table on the board in which data is to be recorded.


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Fathers Farm Data

VegetablesPlanted

Percentage of Vegetables Planted

PredictionsActual

I II III IV V

1. Tomatoes

2. Eggplants

3. Squash4. Okra

5. Ampalaya

Total

f. Each group records actual/accurate data on the board.g. Compare predictions and actual data.h. The group with the most number of correct answers and accurate predictions wins

the game.

2. Review

Review on converting fractions and decimals to percent

Strategy 1: Hi Fraction! Hows Percent? Game

Materials: fraction stripsMechanics:a. Form groups of 6.b. Distribute fraction strips equally among the groups and place them face down in a

pile.c. Pupils look at the top card, name the fraction, and name the percent for the fraction.d. Activity continues till the last card.e. The group with the most number of correct responses wins the game.

Strategy 2: Use common percents

Materials: decimal squares (10ths)Mechanics:a. Distribute assorted squares, face down in a pile to groups.b. Pupils take turns drawing squares.c. All represent the shaded areas as fractions, decimals and percents.d. The group with the most number of correct answers wins.

3. Motivation

Action Song (Body Exercise)

Tune: Are you Sleeping, Dong, Ding, Dong

Title: Fraction to Percent(One-fourth) 4x (Twenty-five) 2x(One-fourth changed to percent) 2x(Twenty-five percent) 2xOne-half = 50%One-fifth = 20%Three-fourths = 75%Two-fifths = 40%


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1. Presentation

Strategy 1: Acting out (concept development)

My Favorite FruitMechanics:a. Divide the class into 8 groups. Each group chooses a leader.b. Present this question: If you were to choose, which fruits would you like to eat

everyday?c. Let each group decide on their favorite fruit among the fruits posted on the board.d. Request the group leaders to stand at the back of the classroom.e. When the teacher gives the signal, the leaders will go to the fruit the group chose.f. Let the leaders explain their choices.g. Let the pupils form the ratios for each fruit chosen: number of groups who chose the

fruit to the total number of groups.h. Convert the ratios to fractions and then to percents.i. Lead the discussion by asking the questions such as:

How many groups are there? 8

How many chose papaya? 2

How do we write this in percent? 25%

We can write: 25% of 8 = 2

We deal with three elements: rate, base, percentage:25 % of 8 = 2

The relationship among the three is:

R x B = P or P = R x B 25 % is the rate. It is given as a percent. It can be expressed as a ratio or fraction

100

25.

8 is called the base. It is a whole number of which you take the percent.2 is called the percentage, meaning a part of the whole. It is the resulting fractional

part of the base.

Other examples are given, like:15% of 575 = NThe teacher will ask:

Which is the percent? 15%

Which is the whole? 575

Which is the part of the whole? N What do you call 15%? Rate.

What do you call 575? Base.

What does N stand for? Percentage.

Strategy 2: Using A Problem Opener

Problem:Seventy-five percent of the 40 pupils of Mrs. Santiago like Mathematics. How many

pupils are Math lovers?

Rate

Base

Percentage


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Mechanics:a. Teacher asks the following questions:

1) How many pupils does Mrs. Santiago have in all?40 is the base.

2) How many percent of the pupils like mathematics?75% is the rate which can be expressed as a ratio or a fraction.

3) How may pupils love mathematics?We are going to solve for this, we represent it by N.

4) How do we translate the problem into an equation?

75% of 40 = N

Rate = 75%Base = 40Percentage = ?

b. Give other problem statements where pupils will identify the rate, base andpercentage?1) 50 % of 40 is what number?2) 25% of 900 = N3) 10 is what percent of 100?4) 85% of 900 = N

Which element is missing in the problem?

Strategy 3: Concept Development

Mechanics:1) Divide the class into 5 groups.2) Teacher will flash mathematical statements or equations like:

80% of 9,475 = N40 is 50% of what number?What number is 16% of 25?25 is what percent of 800?

3) Ask the pupils to identify the given elements in the problems and determine whichelements are missing.

4) Define percentage, rate and base.5) Give more examples of percent problems and let the pupils identify the elements andtranslate them into equations.

6) The group with the most number of correct answers wins.

2. Fixing Skills

A. Identify the related three quantities in problems on percent. Write B for base, R forRate, and P for Percentage.

1. 5% of 24 is 1.2 ___________2. 33% of 260 is 85.8 ___________3. 37.5% of 267 is 100.124 ___________4. 320 is 32% of 1000 ___________

5. 364 is 45.5% of 800 ___________

B. Give the missing quantity. (Base, Rate, Percentage)

1. 8% of 55 is __________

2. 33 % of 116 is __________

3. 18 is 23 % of 1000 __________


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4. Mrs. Mendoza has 50 orchid plants. Thirty five percent are Catleya orchid plants.How many of the 50 orchid plants are catleya?

5. Fifteen percent or one hundred pesos was taken from the Math Club fund formiscellaneous expenses. How much fund available ws Math Club at first?

3. Generalization

Rate is the number written with the word percent or with the symbol %.Base is the total or whole and it is the number that usually follows the phrase percent ofor % of.Percentage is the part of the whole.

C. Application

A. Answer the following questions:1. Which element represents the whole?2. Which represents part of the whole?3. Which element has the symbol %?

B. Identify the Base, Rate and Percentage of the given problem.

Aling Lydia borrowed P25,000 from their cooperative at 12% interest a year. Shepaid P3,000 for the interest.

C. Identify the Base, Rate and Percentage.A department store sold t-shirts at the cost price of P350 with 15% or P52.50 gain.

IV. Evaluation

A. Which statement describes the given element?1. Rate

a. It gives the total of the whole.b. It always has the % sign.c. It gives part of the whole.

2. Percentagea. It names part of the whole.b. It is always written with the percent sign.c. It represents the total number or the whole.

3. Basea. It is the whole from which you take a portion.b. It a part or portion of the whole.c. It is termed as percent.

B. Complete the following sentences to make them true:

1. In the statement 65% of 780 = N, 65% is called the rate because ____________.

2. In 25% of 800 = 200, 200 is the percentage because _________.3. In the statement in No. 2, 800 is the base. It tells __________.

V. Assignment

Write 3 short statements that define rate, base and percentage in your own words.


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a. Almost 70% of the 40 species of Philippine eagle is in danger of extinction. Howmany species is endangered?

b. Let the pupils transform the problem into a simplified form.c. What is 70% of 40?d. Ask them to rename 70% as a fraction or as a decimal. They can solve the problem

in two ways.

0.70 x 40 = 28.00

2

100

70 x1

40 =5

140 or 28

5

e. Provide pupils with more examples. Emphasize the importance of estimation indetermining whether their answers are reasonable. Let them see that 70% is more

than half so their answer should be more than 20 (2

1 of 40).

Strategy 2: Use of A Pie Graph (Graph and Listing)

a. Present the following pie graph of the Gonzales family budget.

food

60% school

supplies

15%

savings

17%

fare

8%

Gonzales family weekly budget of 2000.b. Ask the pupils how they are going to compute for the actual amounts.c. Let them list down the different items and their corresponding allotment.

Food - 60% of 2000 = _______School supplies - 15% of 2000 = ______Fare - 8% of 2000 = _______Savings - 17% of 2000 = _______

d. Let them rename and present as decimal or as a fraction to compute for the actualamounts.

e. Divide the class into four groups and assign an item to each.f. Emphasize the importance of estimation in solving.g. Give more examples of statements with missing percentage.

Strategy 3: Use of concrete objects

a. Present the following situation.

Elmo picked 16 guavas. He sold 25% of them. How many guavas did he sell?

b. Ask a volunteer to draw a picture about the situation.


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Expected illustration

c. Ask: How many guavas did Elmo sell?What percent of the guavas was sold?What is the equivalent fraction / decimal of 25%?

d. Based on the given fraction into how many equal subsets or small groups should theset of guavas be divided?

e. Let the pupils separate the guavas into 4 subsets.Ask: How many are there in each subset?How many guavas did Elmo sell?What elements are given?What element is missing?What formula did we use?

f. To enhance their knowledge let them solve other exercises.

2. Fixing Skills

A. Find each missing number. How many can you give orally?1. 23% of 450 = _____ 4. 10% of 540 = _____2. 50% of 780 = _____ 5. 150% of 200 = _____3. 110% of 48 = _____

B. Use a decimal to find the answer to each problem. Give each answer to the nearesttenth when necessary.1. 13% of 321 = _____

2. 12 % of 460 = _____

3. 45% of 285 = _____4. 33.3T of 210 = _____

5. 16 % of 112 = _____

C. Analyze each problem and solve.1. For her dress making industry, Aling Nena has 40 workers. Forty-six percent of

these workers are man. How many woman workers she have?

3. GeneralizationElicit from the pupils the ways of finding the percent of a given number. Guide them

to generalize that finding the percent of a whole is also finding part of the whole.

C. Application

Strategy: Card Game

Materials: percent cards; one-digit cards from 0-9Mechanics:Divide the pupils into teams. Have a member of each team choose a percent card and twonumber cards to form a two-digit number. Ask the teams to find the percent of the two-digitnumber they formed. If a team answers correctly, the value it obtains automatically becomes


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its score. If not, the members of the other teams have the chance to solve the problems andearn the score for the team. The first team to earn a score of 100 or more wins.

IV. Evaluation

A. Copy and complete.1) 20% of 15

5

1 x 15 =

3) 30 % of 50

10

3x 50 =

5) 35% of 120

0.35 x 120 =

2) 90% of 40

10

9 x 40 =

4) 15% of P 260000.15 x P 26000 =

6) 85% of 600.85 x 60 =

B. Find the value of n.1) 5% of 50 = n3) 2% of 8 = n

5) 10% of 90 = n7) 25 % of 60 = n9) 12% of 150 = n

2) 48% of 250 = n4) 20% of 80 = n

6) 95% of 326 = n8) 92% of 50 = n10) 100% of 21 = n

C. Solve.1. Garrys Garment Factory is progressing. This year, it exported 25% more shoes than last

year. If last year it exported 60,000 pairs of shoes, how many did it exported this year?2. A farmer borrowed P250,000 at 18% yearly interest from the Land Bank to start a poultry

industry. After 6 months, he paid the required interest. At the end of another, 6 months,he paid the whole loan and remaining interest. How much in all did he pay?

V. Assignment

A. Copy and complete each table.

Rate Base Percentage

1) 3% 400 ?

2) 6% 75 ?

3) 15% 20 ?

4) 55% 800 ?

5) 64% 50 ?

Rate Base Percentage

4% 45 ?

8% 37 ?

32% 105 ?

87% 90 ?98% 76 ?

B. Compute for the actual amount using the given data.

Castillo Family income : 12,000.00

Food 60%

Other expenses 35%

Savings 5%

lg math grade 5 - ratl.nos.percent v2.0

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