23 of Perry's savings comprised of 20-cent coins and 50-cent coins. Perry used some 20-cent coins to purchase a kitchen set. The number of 50-cent coins left was 40% more than the number of 20-cent coins left. Given that Perry had 30 more 50-cent coins than 20-cent coins left in the end, find the amount of money Perry spent on the kitchen set.
|
20-cent coins |
50-cent coins |
Before |
2x7 = 14 u |
1x7 = 7 u |
Change |
- 9 u |
|
After |
5x1 = 5 u |
7x1 = 7 u |
Fraction of Perry's savings that comprised of 50-cent coins
= 1 -
23=
13Number of 50-cents coins in the end in percentage
= 100% + 40%
= 140%
140% =
140100 =
75Number of 50-cent coins remains unchanged. Make the number of 50-cent coins the same. LCM of 1 and 7 is 7.
Number of more 50-cent coins than 20-cent coins
= 7 u - 5 u
= 2 u
2 u = 30
1 u = 30 ÷ 2 = 15
Number of 20-cent coins spent on the kitchen set
= 14 u - 5 u
= 9 u
= 9 x 15
= 135
Amount that Perry spent on the kitchen set
= 135 x 0.2
= $27
Answer(s): $27