The ratio of purple to yellow stamps that Jean had was 5 : 4. The cost of each of the purple stamps was $5 and the cost of each of the yellow stamps was $8. Jean sold 20% of the purple stamps and the total cost of the unsold stamps was $468. How many yellow stamps did she have left?
| |
Purple stamps |
Yellow stamps |
| Before |
5 u |
4 u |
| Change |
- 1 u |
|
| After |
4 u |
4 u |
Number of purple stamps sold
= 20% x 5 u
=
20100 x 5 u
= 1 u
| |
Purple stamps |
Yellow stamps |
Total |
| Number |
4 u |
4 u |
|
| Value |
$5 |
$8 |
|
| Total value |
20 u |
32 u |
$468 |
Total cost of unsold stamps
= 20 u + 32 u
= 52 u
52 u = 468
1 u = 468 ÷ 52 = 9
Number of yellow stamps that Jean had left
= 32 u
= 32 x 9
= 288
Answer(s): 288
