Math Word Problems Demystified - A Self Teaching Guide

IMPLEMENTATION: Solve the equation:

4 %xþ 5 %ðxþ 800 Þ¼$ 103

0 : 04 xþ 0 : 05 ðxþ 800 Þ¼ 103

0 : 04 xþ 0 : 05 xþ 40 ¼ 103

0 : 09 xþ 40 ¼ 103

0 : 09 xþ 40 
 40 ¼ 103 
 40

0 : 09 x¼ 63

0 : 091 x

0 : 091

¼

63

0 : 09

x¼$ 700

xþ 800 ¼ 700 þ 800 ¼$ 1500

Hence the person has $700 invested in bonds and $1500 in stocks.

EVALUATION: Find the interest of both investments and then add to see if

the answer is $103. UseI¼PRTwhereT¼1.

Bonds:I¼ 4 %ð 700 Þ¼$ 28

Stocks:I¼ 5 %ð 1500 Þ¼$ 75

$ 28 þ$ 75 ¼$ 103

EXAMPLE:An investor has 3 times as much money invested at 5% as he

has invested at 2% and $600 more invested at 3% than he has invested at

2%. If the total interest from the three investments is $98, find the amounts

he has invested at each rate.

SOLUTION:

GOAL: You are being asked to find the amounts of the three investments.

164 LESSON 15 Solving Finance Problems