Math Word Problems Demystified - A Self Teaching Guide

SOLUTIONS:

1. Letx¼the number of dimes and 3x¼the number of quarters; then the
   value of the dimes is 10xand the value of the quarters is 25 3 xor 75x.

10 xþ 25  3 x¼ 5 : 95  100

10 xþ 75 x¼ 595

85 x¼ 595

851 x

851

¼

595

85

x¼7 dimes

3 x¼ 3  7 ¼21 quarters

2. Letx¼the number of nickels and 18
   x¼the number of pennies;
   then the value of the nickels is 5xand the value of the pennies is
   1 ð 18
   xÞ:

5 xþ 18 
x¼ 38

4 xþ 18 ¼ 38

4 xþ 18 
 18 ¼ 38 
 18

4 x¼ 20

41 x

41

¼

20

4

x¼5 nickels

18 
x¼ 18 
 5 ¼13 pennies

3. Letx¼the number of nickels andxþ 6 ¼the number of quarters; then
   the value of the nickels is 5xand the value of the quarters is 25(xþ6).

5 xþ 25 ðxþ 6 Þ¼ 3  100

5 xþ 25 xþ 150 ¼ 300

LESSON 11 Solving Coin Problems 113