lesson menu main idea example 1:real-world example: solve ratio problems example 2:real-world...
TRANSCRIPT
Main Idea
Example 1:Real-World Example: Solve RatioProblems
Example 2:Real-World Example: Solve RatioProblems
Example 3:Real-World Example: Solve RateProblems
• Solve problems using ratios and rates.
CLUBS Pine Hill Middle School has 300 students. In Zoey’s class, two out of five students belong to a club. Use this ratio to predict how many students at Pine Hill Middle School belong to a club.
Method 1 Use a bar diagram.
Solve Ratio Problems
Step 1 Draw a bar diagram.
There are 60 + 60 or 120 students in two sections.
Solve Ratio Problems
Step 2 Determine how many students are in eachsection.
Solve Ratio Problems
Method 2 Use equivalent fractions.
Write an equivalent ratio.
in a clubtotal
?___25
_____
300= in a club
total
___25
120_____
300=
×60
×60
Since 5 60 = 300, multiply 2 by 60.
Answer: So, you can predict that 120 studentsbelong to a club.
FOOD In a survey, seven out of ten people preferred apple pie over cherry pie. There are 250 people shopping at the grocery store. Use the survey to predict how many people in the store would prefer apple pie.
A. 125 people
B. 150 people
C. 170 people
D. 175 people
SPORTS In a survey, the ratio of students who prefer soccer to baseball is 2 to 3. The number of people who prefer soccer is 36. How many people in the survey prefer baseball?
Solve Ratio Problems
Method 1 Use a bar diagram.
Step 1 Draw a bar diagram.
Solve Ratio Problems
There are 18 + 18 + 18 or 54 people in the survey who prefer baseball.
Step 2 Determine how many people are in eachsection.
________23
3654
=
Solve Ratio Problems
Method 2 Use equivalent fractions.
Write an equivalent ratio.
×18
×18
Since 2 18 = 36, multiply 3 by 18.
soccerbaseball
soccerbaseball
___23
_____
?= 36
Answer: So, 54 people in the survey prefer baseball.
LUNCH PERIODS A survey found that 5 out of every 8 students would prefer an earlier lunch period. If 120 students chose an earlier lunch on the survey, how many students took the survey?
A. 75 people
B. 120 people
C. 192 people
D. 960 people
PET FOOD There are 57 ounces of dog biscuits in 5 boxes. At this rate, how many ounces of dog biscuits are in 8 boxes?
Solve Rate Problems
Method 1 Use a bar diagram.
Step 1 Draw a bar diagram.
Solve Rate Problems
Step 2 Determine the number of ounces in eachsection.
Step 3 Determine the number of ounces that arein 8 boxes.
Solve Rate Problems
Method 2 Use a unit rate.
Step 1 Find the unit rate.
=____________57 ounces5 boxes
___________? ounces1 box
=____________57 ounces5 boxes
___________11.4 ounces1 box
÷5
÷5
Solve Rate Problems
Step 2 Multiply.
11.4 ounces1 box
______________ × 8 boxes = 91.2 ounces
Answer: So, there are 91.2 ounces in 8 boxes ofdog biscuits.
COOKING A recipe for lasagna calls for 15 ounces of ricotta cheese for 12 servings. How many ounces of cheese are needed for 20 servings?
A. 16 ounces
B. 25 ounces
C. 60 ounces
D. 180 ounces
