The ratio of the amount of money that Shiyun and Irene brought along was 4 : 5. For their cousin's present, Shiyun and Irene shared the cost in the ratio of 3 : 2. Shiyun used up
35 of her money to pay for her share. After paying for her share, Irene had $255 left. How much was the present?
|
Shiyun |
Irene |
Before |
4 u |
5 u |
Change |
- 2.4 u |
- 1.6 u |
Comparing the cost shared between Shiyun and Irene |
- 3 p = - 2.4 u |
- 2 p = - 1.6 u |
After |
1.6 u |
255 |
Amount that Shiyun spent on the present
=
35 x 4 u
= 2.4 u
3 p = 2.4 u
1 p = 2.4 u ÷ 3 = 0.8
2 p = 2 x 0.8 = 1.6 u
Amount that Irene had left
= 5 u - 1.6 u
= 3.4 u
3.4 u = 255
1 u = 255 ÷ 3.4 = 75
Cost of the present
= 2.4 u + 1.6 u
= 4 u
= 4 x 75
= $300
Answer: $300