Family Math Studio
Lesson 3.56.AT.3
Compare Ratio Relationships
Compare two ratios by making one amount match or by finding unit rates.
NameDate
Tonight's spark
Chef Reyes makes cocoa with 3 tablespoons of cocoa for 5 ounces of milk. Chef Tran uses 4 tablespoons for 7 ounces of milk. Whose cocoa is more chocolatey?
Make a guess first: does Chef Tran win because 4 is more than 3?
Try it
Work it out on paper. Write one answer on each line.
Which ratio is equivalent to 2:3 and has 12 in the second part?
- A. 8:12
- B. 6:12
- C. 2:12
- D. 12:18
My answer
Recipe A uses 2 tablespoons of cocoa for 4 ounces of milk. Recipe B uses 3 tablespoons for 4 ounces. Which is more chocolatey?
- A. Recipe A
- B. Recipe B
- C. They are the same
My answer
12 cookies are shared equally among 4 children. How many cookies does 1 child get?
- A. 8
- B. 16
- C. 3
- D. 48
My answer
Store X: 3 pens for $6. Store Y: 4 pens for $12. Which store charges less per pen?
- A. Store Y, $3 per pen
- B. Store Y, because $12 is more
- C. Store X, $6 per pen
- D. Store X, $2 per pen
My answer
To compare 3:5 and 4:7 by making the second parts equal, which number can both 5 and 7 scale to?
- A. 12
- B. 35
- C. 57
- D. 2
My answer
Talk about it
Why do the nut amounts have to match before you compare the raisins?
Home mission
Say Chef Reyes's mix out loud: 3 spoons of cocoa for 5 of milk. Ask your student: how much cocoa goes with 10 spoons of milk? With 15? Then ask: why can't we compare Chef Tran's 4 for 7 yet?
If we get stuck, ask
- Are the other amounts the same yet? If not, let's make them equal first.
- Can we find the amount for just 1 by dividing?
- Now that they match, which number is bigger?