Math Word Problems Demystified - A Self Teaching Guide

x¼$600 invested at 2

3

4

%

5 x¼ 5 ð 600 Þ¼$3000 invested at 5

1

2

%

7. Let x¼the amount of money invested at 5% and x
   1300 ¼the
   amount of money invested at 9%.

5 %xþ 9 %ðx
 1300 Þ¼ 219

0 : 05 xþ 0 : 09 ðx
 1300 Þ¼ 219

0 : 05 xþ 0 : 09 x
 117 ¼ 219

0 : 14 x
 117 ¼ 219

0 : 14 x
 117 þ 117 ¼ 219 þ 117

0 : 14 x¼ 336

0 : 141 x

0 : 141

¼

336

0 : 14

x¼$2400 invested at 5%

x
 1300 ¼ 2400 
 1300 ¼$1100 invested at 9%

8. Letx¼the amount of money invested at 7% and 12000
   x¼the
   amount of money invested at 5%.

7 %x¼ 5 %ð12,000
xÞ

0 : 07 x¼ 0 : 05 ð12,000
xÞ

0 : 07 x¼ 600 
 0 : 05 x

0 : 07 xþ 0 : 05 x¼ 600 
 0 : 05 xþ 0 : 05 x

0 : 12 x¼ 600

0 : 121 x

0 : 121

¼

600

0 : 12

170 LESSON 15 Solving Finance Problems