Math Word Problems Demystified - A Self Teaching Guide

EVALUATION: Check the equation:

30 %ð 48 Þ
 30 %ðxÞþ 0 %x¼ 20 %ð 48 Þ

30 %ð 48 Þ
 30 %ð 16 Þþ 0 %ð 16 Þ¼ 20 %ð 48 Þ

14 : 4 
 4 : 8 ¼ 9 : 6

9 : 6 ¼ 9 : 6

The second type of mixture problems consists of mixing two items such as

coffees, teas, candy, etc., with different prices. These problems are similar to

the previous ones. You can use this basic equation:

Item 1Its priceþItem 2Its price¼MixtureIts price

EXAMPLE:A merchant mixes some coffee costing $4 a pound with some

coffee costing $3 a pound. How much of each must be used in order to make

20 pounds of mixture costing $3.75 per pound?

SOLUTION:

GOAL: You are being asked to find how much of each coffee must be mixed

together to get 20 pounds of coffee costing $3.75.

STRATEGY: Letx¼the amount of the $4 coffee and 20
x¼the amount

of the $3 coffee; then

Amount  Price ¼ Total value

Coffee 1 x $4 4(x)

Coffee 2 20 
x $3 3(20
x)

Mixture 20 $3.75 3.75(20)

The equation is 4xþ3(20
x)¼3.75(20).

152 LESSON 14 Solving Mixture Problems