Math Word Problems Demystified - A Self Teaching Guide

EXAMPLE:If a carpet sells for $15.50 per square yard, how much will it cost

to cover a room that measures 20 square yards?

SOLUTION:

GOAL: You are being asked to find the cost of 20 square yards of carpet.

STRATEGY: Write the ratio. It is1sq$^15 ::yd^50 :. The proportion is1sq$^15 ::yd^50 :¼20 sqx:yd:.

IMPLEMENTATION: 1x¼$15.5020;x¼$310. The cost of the carpet

is $310.

EVALUATION:

$ 15 : 50

1

¼

$ 310

20

1 $ 310 ¼$ 15 : 50  20

$ 310 ¼$ 310

EXAMPLE:If 4 gallons of paint can cover 1120 square feet, how many

square feet will 7 gallons of paint cover?

SOLUTION:

GOAL: You are being asked to find how many square feet 7 gallons of paint

will cover.

STRATEGY: Write the ratio. It is 1120 sq4 gallons:ft:. The proportion is

4 gallons

1120 sq:ft:¼

7 gallons

xsq:ft:.

54 LESSON 6 Using Proportions