The ratio of brown to green stamps that Xylia had was 5 : 2. The cost of each of the brown stamps was $3 and the cost of each of the green stamps was $5. Xylia sold 40% of the brown stamps and the total cost of the unsold stamps was $76. How many brown stamps did she have left?
| |
Brown stamps |
Green stamps |
| Before |
5 u |
2 u |
| Change |
- 2 u |
|
| After |
3 u |
2 u |
Number of brown stamps sold
= 40% x 5 u
=
40100 x 5 u
= 2 u
| |
Brown stamps |
Green stamps |
Total |
| Number |
3 u |
2 u |
|
| Value |
$3 |
$5 |
|
| Total value |
9 u |
10 u |
$76 |
Total cost of unsold stamps
= 9 u + 10 u
= 19 u
19 u = 76
1 u = 76 ÷ 19 = 4
Number of brown stamps that Xylia had left
= 9 u
= 9 x 4
= 36
Answer(s): 36
