The ratio of green to white stamps that Tammy had was 4 : 3. The cost of each of the green stamps was $1 and the cost of each of the white stamps was $5. Tammy sold 50% of the green stamps and the total cost of the unsold stamps was $136. How many white stamps did she have left?
| |
Green stamps |
White stamps |
| Before |
4 u |
3 u |
| Change |
- 2 u |
|
| After |
2 u |
3 u |
Number of green stamps sold
= 50% x 4 u
=
50100 x 4 u
= 2 u
| |
Green stamps |
White stamps |
Total |
| Number |
2 u |
3 u |
|
| Value |
$1 |
$5 |
|
| Total value |
2 u |
15 u |
$136 |
Total cost of unsold stamps
= 2 u + 15 u
= 17 u
17 u = 136
1 u = 136 ÷ 17 = 8
Number of white stamps that Tammy had left
= 15 u
= 15 x 8
= 120
Answer(s): 120
