Math Review on Ratios

If there are 5 boys and 7 girls, write the ratio of girls to boys.

• 5 to 7

• 7 to 5

• 5 to 12

• 7 to 12

To disinfect 1 quart of stream water to make it drinkable, you need to add 2 tablets of iodine. How many tablets do you need to disinfect 4 quarts?

• 4 tablets

• 5 tablets

• 6 tablets

• 8 tablets

What are three ways to write a ratio for the amount of dogs compared to the number of cats.

• 7:11

• 11:7

• 11 to 7

• 11/7

• 12 to 7

In an animal shelter, the ratio of cats to dogs is 3 to 5. If there are a total of 25 dogs at the shelter, how many cats do they have?

• 15

• 18

• 21

• 32

Diana uses 30 grams of coffee beans to make 48 fluid ounces of coffee. When guests come, she makes 96 fluid ounces of coffee. How many grams of coffee beans does Diana use when she has visitors?

Mathematical Equivalence

ON

You spend $40 on 5 pounds of concrete. What is the unit rate in dollars per pound?

• $8 per pound

• $5 per pound

• $35 per pound

• 0.125 pounds per dollar

Proportions are __________________.

• a comparison of the same thing

• a linked relationship between different items

• a linked relationship between like items

• two equivalent ratios

If there are 3 boys to 4 girls, then how many boys would there be if there are 20 girls?

• 5 boys

• 10 boys

• 15 boys

• 20 boys

If there are 3 boys to 4 girls, then how many boys would there be if there are 21 students?

• 3 boys

• 6 boys

• 9 boys

• 12 boys

• (4, 16)

• (9, 3)

• (6, 1)

• (16, 4)