lg math grade 5 - ratl.nos.add_sub.dec. v2.0

7/28/2019 LG MATH Grade 5 - Ratl.nos.Add_Sub.dec. 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

Addition and Subtraction of

Decimals

INSTRUCTIONAL MATERIALS COUNCIL SECRETARIAT, 2011


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TABLE OF CONTENTS

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

II. RATIONAL NUMBERS

Addition and Subtraction of Decimals

Adding Decimals ................................................................................................................... 1Subtracting Decimals ............................................................................................................ 3Adding Mixed Decimals with Regrouping ............................................................................. 6Subtracting Mixed Decimals with Regrouping ...................................................................... 11Solving Problems .................................................................................................................. 15Two-Step Word Problems .................................................................................................... 18


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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 Addition andSubtraction of Decimals

Accuracy, Speed Conceptdevelopment, Skill

development

Reading, Speaking,Writing, Games

1. Add and subtract decimals throughthousandths without and withregrouping

Accuracy, Speed Game, Conceptdevelopment

Numbers

2. Add and subtract mixed decimalswith regrouping

Accuracy Modeling, Conceptdevelopment, Acting

out the problem

Cooperative groups,Hands-on activities,

Speaking

Subtract mixed decimals with

regrouping

Accuracy Game, Concept

development

Charts, Cooperative

groups Subtract mixed decimals from whole

numbers

Dignity of labor Conceptdevelopment,

Drawing, Pictures,Flowchart

Independent study,Cooperative groups,

Singing

3. Application of addition andsubtraction of decimals

3.1 Solve word problems involvingeither addition or subtraction ofdecimals including money

Accuracy, Speed,Thoughtfulness,

Thrift

Guess and check,Educated guess,Simplifying the

problem

Reading, Speaking

3.2 Solve 2-step word problemsinvolving addition and subtraction ofdecimals including money

Appreciation Group games,Simplifying the

problem

Movements, Cooperativegroups


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Adding Decimals

I. Learning Objectives

Cognitive: Add decimals through thousandths without or with regroupingPsychomotor: Write the sum of decimals

Affective: Add accurately with speed

II. Learning Content

Skill: Adding decimals through thousandths without or with regroupingReference: BEC-PELC II.G.1.aValues: Accuracy and speed

III. Learning Experiences

A. Preparatory Activities

1. Mental Computation/Drill

Addition of Whole Numbers

Strategy 1: Name the Baby Game

Mechanics:a. Divide the children into group A and B. Each group is subdivided into 4. Each group of 4

stands in one line to give 4 possible pairs of addends of a given sum dictated by theteacher.

b. The teacher says the last name of the baby was 15. The 4 children then takes turn inwriting the addend like 8 + 7, 6 + 9, 10 + 5, 11 + 4.

c. The first group to give the correct addends without duplication gets the point.d. The game continues until all the groups have participated.e. The group that has the most number of points wins the game.

Strategy 2: Traveling Game

Materials: flash cardsMechanics:a. Divide the class into 2 groups. One representative from each group stands at the back of

the classroom.b. Teacher will flash the cards on addition and the first member of each group gives the

sum.c. The player who gives the correct answer first will advance forward with one pace and is

given a point.d. The game continues till all children have participated.e. The group with the most number of points wins.

2. Review

B. Developmental Activities

1. Presentation

Strategy 1: Problem Opener

Nena learned how to cook beef sinigang. She used 0.5 kg of radish and 0.25 kg ofokra. How many kilograms of vegetables did she use?


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Ask the following questions:a. What is asked in the problem?b. What are the given facts?c. What operation is to be used?d. How will you solve the problem?e. If you are to write the given facts in the columns as addends, how do they appear?f. How are the decimal points placed? in one line or disaligned?

Strategy 2: Tossing Dice

Materials: Improvised dice made from leftover woodMechanics:a. Put the following decimals on the four sides of the two dices (1.2, 3.5, 2.6, 4.1, 1.2, 3.3,

1.8, 1.6)b. Toss the two dice together and ask pupils to give the sum of the decimals seen on the

top side of the 2 dice.c. Continue the game for 10 minutes.d. Ask the following: What did you do with the decimals that appeared on the top side of the

2 dice? If you are to add them on the board or on your paper, how do you write them?

2. Fixing Skills

A. Find each sum.

1. 0.31 + 0.602. 0.59 + 0.23. 0.389 + 0.314. 0.015 + 0.3365. 0.635 + 0.6526. 0.59 + 0.347 + 0.3217. 0.368 + 0.4 + 0.398. 0.79 + 0.882 + 0.369. 0.7 + 0.25 + 0.250

10. 0.17 + 0.82 + 0.213

B. Put decimal points in the addends so the sum in each item will be correct.

Addends Sum

1. 346 + 15 = 49.6 = _________________2. 346 + 15 = 36.1 = _________________3. 346 + 15 = 34.75 = _________________4. 346 + 15 = 4.96 = _________________5. 346 + 15 = 18.46 = _________________6. 346 + 15 = 3.61 = _________________

3. Generalization

In adding decimals, how do we write the addends? How are the decimal points placed?

In adding decimals:

1. Arrange the numbers in column,2. Align the decimal point,3. Add like whole number, and4. Put the decimal point directly below the decimal point in the addends.


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IV. Evaluation

Add.1) 2) 3) 4) 5)

25.17+ 8.23

6.14+ 4.76

7.32+ 5.21

8.53+ 9.35 24.5

+ 73.23

V. Assignment

A. Find the sum.1) 2) 3) 4) 5)

3.76

+ 4.356

23.34+ 0.3

0.76+ 0.23

37.786+ 2.632

4.762+ 1.38

B. Read and solve.

A butcher weighed two hogs. One hog weighed 35.45 kg, while the other weighed 41.75

kg. What is the total weight of the two hogs?

Subtracting Decimals


Cognitive: Subtract decimals through thousandths without or with regroupingPsychomotor: Write the difference of decimal numbersAffective: Manifest accuracy and speed in subtracting decimals


Skill: Subtracting decimals through hundredths without or with regroupingReference: BEC-PELC II.G.1.bValue: Accuracy and speed



1. Mental Computation/Drill

Mental computation/drill on basic subtraction facts

Strategy 1: Relay Game

Materials: flash cardsMechanics:a. Divide the class into 4 groups of equal numbers each and form 4 lines at the aisle

between the desks.b. As the teacher flashes the cards one after the other, the members take turn in giving

the correct answer. The member who had answered will go to the end of the line.c. The group that returns to its original formation first is the winner.


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4) 0.5 - 0.05 9) 0.10 - 4.6535) 0.7 - 0.084 10) 0.19 - 0.163

B. Write the missing digit in the.

1. 0. 8-0. 5 2

2. 0. 3- 0. 7 3

3. 0. 3- 0. 1 7

0. 2 5 3 0. 0 9 5 0. 4 1 0

C. Solve.

1. What number when added to 0.2635 will result to 0.333?2. Two sides of a triangle are 0.623 and 0.18 m. If the perimeter is 0.95 cm, find

the third side?3. Using all the digits 0, 1, 3, and 6. What is the difference between the largest and

smallest decimals that can be formed?

3. Generalization

What important points did you learn from todays lesson? What should you remember

when the minuend has less decimal places than the subtrahend?

In subtracting decimals:

1. Arrange the number in column;2. Align the decimal point;3. Subtract like whole number;4. Put the decimal point directly below the decimal point in the minuend and

subtrahend;5. When the minuend has less decimal place than the subtrahend add the number of

zero (0) equal to the decimal places of the subtrahend;6. And subtract as whole number.

C. Application

Find the difference:a) b)

0.762- 0.36

0.936- 0.642

c) Jill cut 0.65 m from a piece of wire 0.92 m long. How long was left of the piece of wire?

IV. Evaluation

Solve for the difference.a) b)

0.3- 0.18

0.4- 0.27

c) What is 0.397 subtracted from 0.74?d) The difference between 0.8 and 0.36 is _____.e) From 0.4 subtract 0.187.


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V. Assignment

Read and solve.1. A farmer has an orchard measuring 0.82 hectare. If 0.543 hectare is planted to mangoes and

the rest to avocadoes, what part is planted to avocadoes?2. Mr. Cruz has a 0.56 hectare land. He allotted 0.198 hectare to build a fishpond. What part of

his land is not allotted to his fishpond?

Adding Mixed Decimals with Regrouping


Cognitive: Add mixed decimals with regroupingPsychomotor: Write mixed decimal addends properly in columnAffective: Value importance of lining up of decimal points accurately


Skill: Adding mixed decimals with regroupingReference: BEC-PELC II.G.2.aMaterials: Flash cards, coinsValue: Accuracy



1. Mental computation

Drill on addition of whole numbers

Materials: flash cards

Example: 23+ 8

41+ 26

35+ 12

70+ 28

2. Review

Adding decimals without or with regrouping

Materials: flash cardsProvide pupils with addends having different number of digits.Example: a) 0.2 + 0.65 + 0.308

b) 0.36 + 0.4 + 0.092

3. Motivation

Game: Find the whole

Materials: Picture cardsMechanics:a. Form 2 groups of five. Line them up.b. Each group will be given cards showing shaded parts.


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Example:

c. The teacher will say: Each card is a part of a whole consisting of ten parts.d. The first pupil in each group will pick a card and the teacher dictates the question.

Example: How many more tenths would have to be added to make a sum greaterthan one?

e. The first pupil who can give the correct answer earns the point.f. The game continues until the last pupil in line.g. The group earning more points is declared the winner.


1. Presentation

Strategy 1: Using concrete objects

Game: Money Matters

Materials: Coins of different denominationsMechanics:a. Form 2 groups of 3.b. Give each group 3 pairs of envelopes.c. At the signal go, the first pupil will open the amount in each and add the coins to get the

total amount.Note: Each envelope should have coins totaling more than 1.00.

d. The first pupil to give the correct total amount earns a point.e. The group with more points earned wins the game.

Discussion of the Activity:

a. Going back to the examples used in the class activity: What amounts have you recorded for the 1st pair of envelopes? What total amount did you get for the two?

b. Teacher reflects the answers on the board.Example: 2.25

+ 1.75

4.00c. The teacher continues asking same set of questions for the next 2 pairs of envelopes and

at the same time.d. Write the answers on the board.e. You may ask the following:

What did you notice with the digits that have the same place value? What about the decimal points?

Do we add decimal numbers the way we add whole numbers? Was there regroupingdone?

f. Lead the pupils in discovering the rules to follow in adding mixed decimals withregrouping.

g. For Higher Order Thinking Skills (HOTS), the teacher may ask: Why is it so important toline up decimal points accurately?

(To keep the proper place value of the digits in the number.)


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Strategy 2: ModelingMaterials: Grid papers (Flats 100 squares)Using a problem opener:

Armani and Julius went fishing. They caught 2 big fish weighing 2.15 kg and 1.95 kg.What is the total weight of the 2 fish?a. The teacher may ask some comprehension questions.b. Guide the pupils in analyzing the problem by asking:

What are given?

What is being asked?c. Help them plan what to do. Ask: What should you do to find the answer to the

questions? What is the number equation?d. Let the pupils write their equation on the board. (2.15 + 1.95 = N)e. Show a flat and say: If this represents 1 kg, how will you represent 2.15 kg? 1.95 kg?

(For 2.15 2 flats and shade 15 of the 100 squares or .15, for 1.95 1 flat and shade 95of the 100 squares or .95)

f. Elicit from the pupils; to find the total, the flats must be put together and also the shadedparts. (As shown in the figure A.)

1 2

0.95 0.15

Figure A

Put together the 95 and 15 shaded squares, by crossing out five squares from the 15

squares and combining them with the 95 squares.

Ask: What did we actually do (we regroup). What did we form?(1 flat and 10 shaded squares.)


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1 flat 10 out of 100 or .10

Figure B

Using the models, what is the sum of 1.95 and 2.15? (4 flats and 10 shaded squares)This means in symbol 4.10.Write the equation onthe board:

The teacher asks some analysis questions:

What did you notice with the digits with the same place value?

What about the decimal points?

How are they arranged?

Do we add decimal numbers just like adding whole numbers?

Was there regrouping done?Lead the pupils in discovering the rules in adding mixed decimals with regrouping.Give some additional practice exercises.

2. Fixing Skills

A. Find each sum.

1) 3.9 + 6.27

2) 40.59 + 1.23) 38.69 + 6.314) 1.015 + 3.365) 63.08 + 2.6526) 2.59 + 6.347 + 32.577) 3.368 + 20.4 + 10.398) 6.79 + 2.882 + 3.69) 25.07 + 1.25 + 5.25010) 4.17 + 5.82 + 5.213

B. Put decimal points in the addends so the sum in each item will be correct.

Addends Sum

1) 346 + 15 = 49.6 = _________________2) 346 + 15 = 36.1 = _________________3) 346 + 15 = 34.75 = _________________4) 346 + 15 = 4.96 = _________________5) 346 + 15 = 18.46 = _________________6) 346 + 15 = 3.61 = _________________

1.95+ 2.15


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C. Write in column and add.

1) 50.92 + 12.692) 59.50 + 39.783) 85.25 + 46.654) Combine 35.963 and 16.345) What is 6.387 more than 5.201?

3. Generalization

How do we add mixed decimals with regrouping?

Write the numbers in column putting the digits that have the same place value in onecolumn.

Line up decimal points.

Start adding the digits with the least place value. Regroup if the sum of the figures inone column exceeds 10. Add the numbers the way you add whole numbers.

C. Application

A. Add the following

1) 4.38 2) 2.485 3) .28+ 4.79 +4.25 + 2.85

34.8

4) 28 + 12.59 + 2.785) 18.30 + 7 + 9.65

B. Find the perimeter of each figure.

C. Solve

1) Jerry has to save money to buy spare parts for his bicycle. The parts cost 138.25,320 and 73.50. How much money does he need to save?

2) Monet has the following average monthly expenses: 1250.50 gasoline, 3050.95for food, 600.00 for parking and toll fees and 2700 for lodging. What is her total

monthly expenses?3) Rainfall in the last quarter of one year was recorded as follows: October, 6.28 cm;

November, 5.98 cm; and December, 4.16 cm. How much rain fell during the quarter?

IV. Evaluation

A. Arrange in column and add:

1) 8.6 + 7.4 + 9.35 = N2) 4.521 + 1.46 + 2.8 = N

O P

Q R

18.15 cm 19.25 cm

12 m

25.2 cm

S U

T

29.03 m

38.42 m

42.3 m


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3) What is 2.37 added to the sum of 8.56 and 3.7?4) If 5.6 added to 3.48, what is the sum?5) In selling newspapers, Jan earned 58.25 on Monday, 83.50 on Wednesday, and

79.65 on Friday. How much did Jan earn in 3 days?

B. Write the missing numbers in each column.

1) 9.86 2) 2.890+ 2.47 1.5

1.211 .261

8.44

3) 5.64 4) 3.34+ 4.96 .3

10.00 4.201

9.0635) .2

1.272.978

9.614

V. Assignment

A. Find the sum:1) 38.66 + 52.87 =2) 42.03 + 909.5 =3) 71.68 + 12.338 =4) 67.009 + 40.992 =5) 347.21 + 2.098 + 92.3 =

B. Write the missing addend or sum.1) 33.45 + 14.25 =2) ____ + 174.6 = 211

3) 5.062 + 3.095 = ____4) 9.6 + 3.095 = ____5) ____ + 21.99 = 41.00

C. Complete the Decimal Magic Square so that the sum along a row, a column, or a diagonal isthe same.

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5.2

3.5

Subtracting Mixed Decimals with Regrouping


Cognitive: Subtract mixed decimals with regroupingPsychomotor: Write the difference of the given mixed decimalsAffective: Subtract mixed decimals with and without regrouping with accuracy


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Skill: Subtract mixed decimals with regroupingReference: BEC-PELC II.G.2.bMaterials: Flash cardsValue: Accuracy, working willingly, thrift



1. Mental computationDrill on subtraction from multiples of 10

Strategy 1: Concentration Game

Materials: 10 Subtraction cards with minuends of multiples of 10 like the examplesbelow

50- 27

30- 16

20- 12

60- 23

40- 18

80- 48

70- 56

90- 56

10- 4

50- 25

10 answer cards for the subtraction cards above

23 14 8 37 22 32 14 34 6 25

Mechanics:a. Mix up the 20 cards and lay them face down in four rows with five cards in back row.b. Take turns.c. Turn over two cards. If the subtraction sentence card matches with the answer card,

keep the cards.

d. If the cards do not match, turn them over.e. After each player has had four turns, the player with the greater number of cards isthe winner.

Strategy 2: Traveling game. Drill on basic subtraction facts.

Materials: Flash cardsMechanics:a. Pupils are grouped into four. (in column)b. A pupil arbiter will flash a subtraction card and the first representative from each

group stands at the back of the room to answer the equation.c. The first to answer correctly among them takes one pace forward.d. The pupil who reaches the front first wins and the group gets a point.

e. The game continues until all the members have participated.f. The group with most points wins.


1. Presentation

Strategy 1: Problem opener (written on a manila paper)

Mother has 8.5 kg of flour. She used 2.3 kg in cooking kutsinta. How many kg offlour were left?


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Ask these questions:a. What is asked in the problem?b. What are the given data?c. What process are you going to use?d. What is the mathematical sentence?e. Solve the problem. Show the solution.

8.5- 2.3

6.2f. What is the first step done? Align first the decimal points.g. What is step 2? Subtract the decimal, starting from the right most digits.

Strategy 2: Comparing the height of 2 girls

Milas height is 89.2 cm. Emilys height is 78.6 cm. By how many centimetres is Milataller than Emily?

Ask the following:

a. What is asked?

b. What are the given facts?c. What process is to be used?d. What is the mathematical sentence?e. Solve the problem.

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89.2- 78.6

f. What did you do to be able to subtract?

2. Fixing Skills

A. Find each difference.

1. 5.3 - 1.8 6. 5.094 - 2.5232. 3.28 - 1.59 7. 8.03 - 5.13. 7.0 - 3.12 8. 6.3 - 5.944. 20.5 - 1.501 9. 10.2 - 4.6535. 6.7 - 3.98 10. 110.191 - 1.163

B. Write the missing digit in the.

1. 6. 8-2. 5

2. 4. 3- 0. 7

3. 2. 3- 1 7. 1

4. 2 5 4. 0 9 6 5. 4 1C. Perform as indicated. Do the work in the parenthesis first.

1. (57.31 - 29.54) - 12.37 = N2. 200.09 - (121.25 - 88.011) = N3. (107.05 - 38.11) - (12.62 - 9.25) = N

3. Generalization

What should be done when the last two digits from the right of the subtrahend aregreater than the minuend? (Regrouping is done)


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C. Application

Two groups of fifth grades had a softball-throwing contest. The tables show how eachpupil threw the ball.

Group I Group 2

Name Distance Name DistanceJohnMaryJunBob

Cathy

10.68 m11.56 m

11.459 m8.09 m7.6 m

LisaCarolMikeAmyJack

9.993 m12.834 m

13.1 m10.3 m8.29 m

Use the table to find each answer.

1. How much farther did Jun throw than Bob?2. How much farther did Jun throw than Cathy did?3. Who threw the ball farther than Jun?4. How much shorter was Lisas throw than Johns? 5. How much shorter was Marys throw than Carols?6. What was the difference between the longest and the shortest throw in group 2?

A. Write in column and subtract.

1. Subtract 25.963 from 114.042. Take away 83.12 from 200.3. From 215, subtract 65.0694. 69.12 - 35.855. 2051.53 - 615.75

B. Write or = on the blank to make each sentence true.

1. 3.63 - 1.95 _____ 1.65

2. 9.87 - 5.68 _____ 4.193. 6.65 - 3.56 _____ 2.094. 7.58 - 6.09 _____ 1.945. 28.11 - 16.238 _____ 11.872

C. Solve.

1. Who am I? If you add me to 15.6, you get 40.98?2. At the start of a trip. Alfie noted that her odometer (mileage indicator) read 16875.2

km. After he finished the trip, it read 18169.5 km. How far did she drive?3. A bag and sign pen cost 153.75. The bag costs 28.85 more than the sign pen.

How much does each cost?

IV. Evaluation

A. Find the difference:

3) If 18.0039 is taken away from 32.2746, what is left?4) What is left if 29.87 is taken from 59.10?5) (67.32 - 29.56) - 18.47 = N

1) 9.99- 4.56

2) 41.2- 25.7


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V. Assignment

Read and solve.

1. Sol ran the 100-m dash 0.68 seconds faster than the 18.32-seconds record set by Tina lastyear. How many seconds did Sol run the 100-m dash?

2. A pair of sports shoes costs 308.35. Wally has saved only 189.50. How much moredoes he need to buy the shoes?

3. A barangay has a total road length of 184.53 km. If 109.97 km of this had been paved, howmuch more remains to be paved?

Solving Problems


Cognitive: Solve word problems involving either addition or subtraction of decimals includingmoney

Psychomotor: Write the correct equation in solving a given problem involving either addition orsubtraction of decimals including money

Affective: Work accurately under time pressure, thoughtfulness, thriftiness


Skill: Solving word problem involving either addition or subtraction of decimalsincluding money

Reference: BEC-PELC II.G.3.1Materials: chartsValue: Speed and accuracy



1. Drill

Mental Computation: Answer orally

24 24 + 13 =16 16 7 =

82 82 24 =39 39 + 25 =

65 65 27 =

Strategy 1: Decision Making

Guess and check educated guess

Materials: Problems written on a Manila PaperMechanics:

a. The teacher will group the pupils into 2. To one side of the board is the addition sign andon the other side is the subtraction sign.

b. As the teacher posts a problem on a Manila paper, the pupils will decide whether they willuse addition or subtraction. Those who think that they will use addition, will go to theaddition side and those who think the process to be used is subtraction, will go to thesubtraction side.

c. Analysis of the problem will follow to determine which of the 2 groups is correct.


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d. The process goes on till at least 5 problems were presented.

2. Review


1. Presentation

Strategy 1: Using a problem opener

Simplifying the problem/linguistic reading, speaking

It was Mothers birthday. Nina gave her a pair of slippers that cost 55.50 and abandana worth 27.75. How much in all did Nina spend for the gifts?

a. What did Nina buy for her mother?b. How much is each gift?c. What is the operation to be used?d. Can you transform the problem into a mathematical sentence? Do it.e. Solve and label your answer.

Strategy 2

The distance from Vigan to Laoag is 82.29 km. The distance from Vigan to Baguio is195.6 km. How much farther is Baguio than Laoag from Vigan?

a. What is the process to be used?b. What is the mathematical sentence?c. Show the solution on the board and solve.d. If you are asked to travel which of the two places do you want to visit? Why?

Strategy 3

Aling Auring charged Mrs. Santos 257.25 for the uniforms of her children. Mrs. Santospaid 300. How much is her change?

a. What is asked in the problem?b. What are the given facts?c. What is the process to be used?d. What is the mathematical sentence?e. Solve the problem.f. What is the answer?

2. Fixing Skills

Solve the following skills.

1. Anton is buying supplies for her school project. The items he is buying and their pricesare listed below. What is the total cost of the items?

Illustration board - 22.45Pentel Pen - 98.70Art Papers - 15.65Glue - 35.95

2. A triangle has sides measuring 3.25 cm, 5.275 cm, and 6.1 cm. What is its perimeter?


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3. In a sale, a cellphone was sold at 2681.25. If its regular price was 3575, how muchless was the sale price?

4. Alvin bought a bunch of flowers for 140.50. If she gave a 100 bill and a 50 bill, howmuch was her change?

3. Generalization

What steps did you learn to solve a mathematical problem? What clues will help youdetermine the process to be used? (addition: altogether, in all, combine, and, etc.)(Subtraction: left, remain, difference, how much more/farther)

There are steps to follow in solving mathematical problem:

1. Analyze the word problem by identifying:a. What is askedb. What are given facts

2. Decide the process3. Write the mathematical sentence

4. Solve the problemC. Application

Solve the following problems:

1. A metre measures about 39.37 inches. How much longer is a metre than a yard?2. John drove 48.62 km in the first hour, 38.95 km in the 2

ndhour, and 41.96 km in the third

hour. How far did he drive in 3 hours?

IV. Evaluation

Solve the following problems:

1. Ellen has 7.35 while her brother has 4.95. How much money do they have? How much moredoes Ellen have than her brother?

2. A meat vendor has 56.8 kilos of pork. She sold 49.5 kilos. How many kilos were left?3. A tree 10.5 metres high broke during the storm. The broken part measured 3.75 metres. How

tall was the remaining part?4. At enrolment time, Mrs. Cruz paid 825.50 for Nenas fees, 637.80 for Carlitos fees, and

425.75 for Cecilles fees. What was the total amount she spent for the fees?

V. Assignment

Analyze and solve the problem.

Mrs. Flores bought 3 chickens weighing 2.7 kilos, 1.8 kilos and 2.2 kilos each. What was the totalweight of the three chickens?


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Two-Step Word Problems


Cognitive: Solve word problems involving addition and subtraction of decimals includingmoney

Psychomotor: Write the equation and solution in solving two-step word problems involvingaddition and subtraction of decimals including money

Affective: Appreciate different ways of solving a problem


Skill: Solving word problems involving addition or subtraction of decimals includingmoney

Reference: BEC-PELC II.G.3.2Materials: Charts where problems are writtenValue: Appreciation



1. Mental computation

If your mother gives you 20.00 for your daily allowance, how much is your weeklyallowance?

2. Review or Drill

Strategy: Agawan ng Panyo

Materials: Flash cards, handkerchiefMechanics:

a. Ask for a tall volunteer pupil to stand in front, at the center. He or she is the arbiter.He or she holds the handkerchief and lets it dangle in his or her hand.

b. Divide the class into 2 groups. Ask the first two pupils of each team to stand at thecenter at the back of the room. They are then the first to give the answer.

c. Teacher flashes an equation like 42 + 20 = 62.d. The pupils who get the handkerchief first will give the answer. The team gets the

point if his answer is correct. The pupils from the other team may get the point ifthe answer previously given is incorrect.

e. Continue the game until most of the pupils have participated. The team with the mostnumber of points wins.


1. Presentation

Strategy 1: Problem opener

Simplifying the problem/cooperative group

Materials: written on manila paper


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Problem Number 1

Jacob bought a pair of shoes for 245, a pair of socks for 42.75 and trousers for526.99. He gave the cashier a thousand-peso bill. How much change did he receive?

a. What is asked in the problem?b. What are the given facts?c. What is the hidden information?d. What are the processes to be used?e. What is the mathematical sentence?f. Solve the problem and label the answer.g. Look back if the answer makes sense.

Problem Number 2

Mang Andrew has 8.25 kg of tomatoes to sell in the market. In the morning, he sold4.75 kg while he sold 2.25 kg in the afternoon. How many kilograms of tomatoes wereleft?

a. What is asked in the problem?

b. What are the given facts?c. What is the hidden information?d. What are the processes to be used?e. What is the mathematical sentence?f. Solve the problem and label the answer.g. Look back if the answer makes sense.

Problem Number 3

Last Saturday, Anna went to a bookstore and bought the following items: a pocketbook which cost 23.75, a set of colored pens which costs 36.20 and a liquid paperwhich costs 23.95. If she gave a 100-bill to the cashier, how much change did shereceive?

a. What is asked in the problem?b. What are the given facts?c. What is the hidden information?d. What are the processes to be used?e. What is the mathematical sentence?f. Solve the problem and label the answer.g. Look back if the answer makes sense.

2. Fixing Skills

Solving the following problems.

1. The perimeter of a quadrilateral is 412.95 cm. If the three known sides measure85.56 cm, 112.77 cm and 85.26 cm, how long is the fourth side?2. I bought 4 items worth 39.90, 68.60, 58.75 and 120.25. How much change

will I get from a 500-bill?3. A rectangle is 13.8 long and 9.7 cm wide. Find its perimeter.

3. Generalization

What are the things needed to be able to solve a problem? Do you need to solve thehidden question first? Why? Which of the 2 operations used should be done first?


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C. Application

Group the pupils into 4 and give them different problems written on strips of paper. Let theleader stand to draw lots on the problem that are to be solved by each group. They thenexplain their group work.

IV. Evaluation

Study the following menu in a canteen and answer the question that follows:

1. Arnel paid 50.00 for nilaga and rice. How much was his change?2. Ayen ordered palabok and gulaman. How much was her change with her 100-bill?

3. Mrs. Lopez ordered rice, pinakbet and fried fish. She gave 100. How much was herchange?4. Kate gave 50 for spaghetti and mango juice. How much is her change?5. It was Tinas birthday. She ordered spaghetti, palabok, mango juice and gulaman. If she

paid a hundred peso-bill and gave a tip of 5.00, how much will be her change?

V. Assignment

Solve the following.

1. AJ earned 35.50 for selling newspapers and he earned 32.50 for selling sampaguitagarlands. He paid 52.75 for a pad paper and a ballpen. How much money had he left?

JM visits his dentist every six month. He paid his dentist 500 for dental treatment and

450 for prophylaxis. How much change did he get from 1000?

MenuSpaghetti 23.75 Mango Juice 7.50Palabok 21.50 Gulaman 6.00Lugaw 8.50 Nilaga (pork) 22.50Rice 5.00 Pinakbet 15.00

Fried fish 12.00

lg math grade 5 - ratl.nos.add_sub.dec. v2.0

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