The ratio of purple to pink stamps that Pamela had was 5 : 4. The cost of each of the purple stamps was $1 and the cost of each of the pink stamps was $2. Pamela sold 20% of the purple stamps and the total cost of the unsold stamps was $24. How many purple stamps did she have left?
| |
Purple stamps |
Pink 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 |
Pink stamps |
Total |
| Number |
4 u |
4 u |
|
| Value |
$1 |
$2 |
|
| Total value |
4 u |
8 u |
$24 |
Total cost of unsold stamps
= 4 u + 8 u
= 12 u
12 u = 24
1 u = 24 ÷ 12 = 2
Number of purple stamps that Pamela had left
= 4 u
= 4 x 2
= 8
Answer(s): 8
