The ratio of the amount of money that Marion and Gem brought along was 3 : 4. For their cousin's present, Marion and Gem shared the cost in the ratio of 2 : 3. Marion used up
25 of her money to pay for her share. After paying for her share, Gem had $275 left. How much was the present?
|
Marion |
Gem |
Before |
3 u |
4 u |
Change |
- 1.2 u |
- 1.8 u |
Comparing the cost shared between Marion and Gem |
- 2 p = - 1.2 u |
- 3 p = - 1.8 u |
After |
1.8 u |
275 |
Amount that Marion spent on the present
=
25 x 3 u
= 1.2 u
2 p = 1.2 u
1 p = 1.2 u ÷ 2 = 0.6
3 p = 3 x 0.6 = 1.8 u
Amount that Gem had left
= 4 u - 1.8 u
= 2.2 u
2.2 u = 275
1 u = 275 ÷ 2.2 = 125
Cost of the present
= 1.2 u + 1.8 u
= 3 u
= 3 x 125
= $375
Answer: $375