The ratio of gold to pink stamps that Emma had was 5 : 2. The cost of each of the gold stamps was $5 and the cost of each of the pink stamps was $7. Emma sold 20% of the gold stamps and the total cost of the unsold stamps was $374. How many gold stamps did she have left?
| |
Gold stamps |
Pink stamps |
| Before |
5 u |
2 u |
| Change |
- 1 u |
|
| After |
4 u |
2 u |
Number of gold stamps sold
= 20% x 5 u
=
20100 x 5 u
= 1 u
| |
Gold stamps |
Pink stamps |
Total |
| Number |
4 u |
2 u |
|
| Value |
$5 |
$7 |
|
| Total value |
20 u |
14 u |
$374 |
Total cost of unsold stamps
= 20 u + 14 u
= 34 u
34 u = 374
1 u = 374 ÷ 34 = 11
Number of gold stamps that Emma had left
= 20 u
= 20 x 11
= 220
Answer(s): 220
