Solving Word Problems Using Proportions

Review: Solve the following proportion using cross multiplication

Now that you know how to solve proportions using cross products, lets apply the same process to solving word problems using proportions.

Required Steps:Set up proportion - write labels in frontCross multiplyDivide both sides by coefficient (number attached to variable)Circle final answer

Examples: Calculator permitted, but show required steps.

1.) If 2 tires cost $74, how much will 5 tires cost?

2.) A car uses 5 gal of gasoline to travel 150 mi. How much gasoline will it use to travel 5 mi? (write final answer as a fraction in lowest terms)

3.) For every 5 sailboats in a harbor, there are 3 motorboats. If there are 30 sailboats, how many motorboats are there?

4.) Davis bought 4 tires for his car at a cost of $262.35. How much would 5 tires cost at the same rate? (round to the nearest cent)

* 5.) A ribbon cost $3.00 for 18 inches. Find the cost of 5 feet of ribbon.

6.)

Demonstrate Understanding: Calculator permitted, but show required steps.

1.) If 3 pairs of jeans cost $117, how many pairs of jeans could you buy for $312?

2.) There are 50 calories in 4 oz of juice. How many calories are there in 14 oz of juice?

3.) Researchers marked 35 black bears. They then captured a sample of 218 black bears. What is an estimate of the black bear population in the area if 25 of the black bears captured were tagged?