Solving Problems with Proportions

Solve for x 

• x = 15
• x = 11
• x = 1/11
• x = 20

A recipe calls for 2 cups of flour for every 3 cups of sugar. How many cups of flour are needed if you use 9 cups of sugar?

• 4 cups

• 6 cups

• 8 cups

• 12 cups

Solve for x

• x=6
• x =1/6
• x = 7
• x=9

In a classroom, the ratio of boys to girls is 4:5. If there are 20 boys, how many girls are there?

• 16

• 20

• 25

• 30

A map scale shows that 1 inch equals 10 miles. How many miles are represented by 7.5 inches on the map?

• 75 miles

• 65 miles

• 55 miles

• 45 miles

For every 8 ounces of water, a solution requires 2 ounces of a chemical. How many ounces of the chemical are needed for 32 ounces of water?

• 4 ounces

• 6 ounces

• 8 ounces

• 10 ounces

A fruit salad recipe calls for 3 parts apples to 2 parts oranges. If you use 12 apples, how many oranges do you need?

• 6

• 8

• 10

• 12

In a survey, the ratio of people who prefer tea to those who prefer coffee is 5:3. If 40 people prefer tea, how many people prefer coffee?

• 24

• 30

• 32

• 48

A school's student to teacher ratio is 20:1. If there are 400 students, how many teachers are there?

• 10

• 20

• 30

• 40

A car travels 120 miles in 3 hours (with a constant speed).  How long will it take a car to travel 200 miles?

• 6 hours
• 5 hours
• 4 hours
• 1 hour