Understanding Ratios
What is a ratio?
A comparison of two quantities
Find an equivalent ratio to 2:3.
4:6 (answers may vary)
10 apples cost $5. What is the unit rate?
$0.50 per apple
A class has 4 boys and 6 girls. What is the ratio of boys to girls?
4:6 (or 2:3 simplified)
A ratio is 2:5. If the total is 14, how many are in the first group?
4
Write the ratio of 2 cats to 5 dogs.
2:5
Is 3:4 equivalent to 6:8?
Yes
A car travels 60 miles in 2 hours. What is the unit rate?
30 miles per hour
A recipe uses 2 cups of juice for every 1 cup of water. How much water is needed for 6 cups of juice?
3 cups
A recipe uses 3 cups of flour for 6 servings. How much flour is needed for 12 servings?
6 cups
Write the ratio 6 to 3 as a fraction.
6/3
Fill in the blank: 5:2 = 10:__
4
12 pencils cost $6. What is the cost per pencil?
$0.50 per pencil
There are 3 red marbles for every 2 blue marbles. If there are 6 red marbles, how many blue marbles are there?
4 blue marbles
The ratio of cats to dogs is 1:2. If there are 18 animals total, how many are dogs?
12 dogs
Simplify the ratio 10:2.
5:1
Find a ratio equivalent to 7:1.
14:2 (answers may vary)
A student reads 24 pages in 3 days.
How many pages per day?
8 pages per day
A map uses 1 inch to represent 2 miles. How many miles is 5 inches?
10 miles
A student says 2:3 and 4:9 are equivalent. Are they correct? Why or why not?
No, because 2:3 ≠ 4:9
Which is a correct way to write a ratio?
a. 3:4
b. 3/4
c. 3 to 4
d. all of them
All of them
Is 4:5 equivalent to 8:12? Explain.
No (8:12 simplifies to 2:3)
15 cookies are made in 5 minutes. How many cookies per minute?
3 cookies per minute
A bag has a ratio of 5 green to 3 yellow marbles. If there are 40 marbles total, how many are green?
25 green
A store sells 3 notebooks for $6. Another sells 5 notebooks for $10. Which is the better deal? Explain.
Same deal (both $2 per notebook)