The ratio of red to gold stamps that Shannon had was 4 : 3. The cost of each of the red stamps was $3 and the cost of each of the gold stamps was $4. Shannon sold 50% of the red stamps and the total cost of the unsold stamps was $162. How many gold stamps did she have left?
| |
Red stamps |
Gold stamps |
| Before |
4 u |
3 u |
| Change |
- 2 u |
|
| After |
2 u |
3 u |
Number of red stamps sold
= 50% x 4 u
=
50100 x 4 u
= 2 u
| |
Red stamps |
Gold stamps |
Total |
| Number |
2 u |
3 u |
|
| Value |
$3 |
$4 |
|
| Total value |
6 u |
12 u |
$162 |
Total cost of unsold stamps
= 6 u + 12 u
= 18 u
18 u = 162
1 u = 162 ÷ 18 = 9
Number of gold stamps that Shannon had left
= 12 u
= 12 x 9
= 108
Answer(s): 108
