Applications of Proportions

The ratio of boys to girls in history class is 4 to 5. How many girls are in the class if there are 12 boys in the class?

• 12 girls

• 15 girls

• 5.3 girls

• 27 girls

A cake recipe calls for 1.5 cups of milk and 3 cups of flour. Seth made a mistake and used 5 cups of flour. How many cups of milk should he use to keep the proportions correct?

• 2.5 cups milk

• 1.75 cups milk

• 2 cups flour

• 2.25 cups milk

Hint: Draw a picture of the scenario and label the diagrams to assist in solving the real world problem.

• 30.8 ft

• 34 ft

• 25.2 ft

• 36 ft

Two ratios that are equal are

• similar sides

• unit rates

• congruent

• proportional

COMPUTERS About 13 out of 20 homes have a personal computer. On a street with 60 homes, how many would you expect to have a personal computer?

• 39 Computers

• 4.3 Homes

• 39 Homes

• 4.3 Computers

Solve the proportion

• x = 3

• x = -3

• x = 1

• x = -1

A cake recipe calls for 1.5 cups of milk and 3 cups of flour. Seth made a mistake and used 5 cups of flour. How many cups of milk should he use to keep the proportions correct?

• 2.5 cups milk

• 1.75 cups milk

• 2 cups flour

• 2.25 cups milk

If it costs $13.50 for 5 notebooks, how much will it cost for 8 notebooks?

• $2.70

• $21.60

• $18.50

• $67.50

In a shipment of 400 parts, 14 are found to be defective. How many defective parts should be expected in a shipment of 1000?

• 2.5 parts

• 28 parts

• 50 parts

• 35 parts

The sap of maple trees is used to make maple syrup. One gallon of maple syrup takes 40 gallons of sap. Write and solve a proportion to find the number of gallons of maple syrup that can be made from 1520 gallons of sap.

• 60,800 gallons

• 40 gallons

• 1540 gallons

• 38 gallons