Pre-Algebra Demystified

Word Problems

The following procedure can be used to solve word problems involving measure-

ment:

 Step 1 Read the problem and decide what you are being asked to find.

 Step 2 Select the correct conversion factor or factors.

 Step 3 Multiply or divide.

 Step 4 Complete any additional steps necessary.

EXAMPLE

Find the cost of 24 feet of rope if it costs $0.59 per yard.

SOLUTION

Change 24 ft to yards:

24 ft3ft¼8yd

Find the cost of 8 yd:

$0.59 8 ¼$4.72

Hence, 24 feet of rope will cost $4.72.

EXAMPLE

If a gallon of oil costs $4.95 and a quart of oil costs $1.79, how much is saved

by buying the oil in gallons instead of quarts if a person needs 3 gallons of

oil?

SOLUTION

Cost of 3 gallons of oil

$4.95 3 ¼$14.85

Change 3 gallons to quarts:

3 gal4qt¼12 qt

Cost of 12 qt of oil

$1.79 12 ¼$21.48

Subtract:

$21.48
$14.85¼$6.63

Hence, a person can save $6.63 by buying the oil in gallons instead of quarts.

198 CHAPTER 10 Measurement