The ratio of white to purple stamps that Kylie had was 5 : 2. The cost of each of the white stamps was $4 and the cost of each of the purple stamps was $6. Kylie sold 20% of the white stamps and the total cost of the unsold stamps was $56. How many purple stamps did she have left?
| |
White stamps |
Purple stamps |
| Before |
5 u |
2 u |
| Change |
- 1 u |
|
| After |
4 u |
2 u |
Number of white stamps sold
= 20% x 5 u
=
20100 x 5 u
= 1 u
| |
White stamps |
Purple stamps |
Total |
| Number |
4 u |
2 u |
|
| Value |
$4 |
$6 |
|
| Total value |
16 u |
12 u |
$56 |
Total cost of unsold stamps
= 16 u + 12 u
= 28 u
28 u = 56
1 u = 56 ÷ 28 = 2
Number of purple stamps that Kylie had left
= 12 u
= 12 x 2
= 24
Answer(s): 24
