The ratio of purple to black stamps that Xylia had was 5 : 4. The cost of each of the purple stamps was $2 and the cost of each of the black stamps was $6. Xylia sold 20% of the purple stamps and the total cost of the unsold stamps was $384. How many purple stamps did she have left?
| |
Purple stamps |
Black 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 |
Black stamps |
Total |
| Number |
4 u |
4 u |
|
| Value |
$2 |
$6 |
|
| Total value |
8 u |
24 u |
$384 |
Total cost of unsold stamps
= 8 u + 24 u
= 32 u
32 u = 384
1 u = 384 ÷ 32 = 12
Number of purple stamps that Xylia had left
= 8 u
= 8 x 12
= 96
Answer(s): 96
