The ratio of the amount of money that Dana and Mary brought along was 3 : 4. For their brother's gift, Dana and Mary shared the cost in the ratio of 2 : 3. Dana used up
25 of her money to pay for her share. After paying for her share, Mary had $242 left. How much was the gift?
| |
Dana |
Mary |
| Before |
3 u |
4 u |
| Change |
- 1.2 u |
- 1.8 u |
Comparing the cost shared
between Dana and Mary |
- 2 p =
- 1.2 u |
- 3 p =
- 1.8 u |
| After |
1.8 u |
242 |
Amount that Dana spent on the gift
=
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 Mary had left
= 4 u - 1.8 u
= 2.2 u
2.2 u = 242
1 u = 242 ÷ 2.2 = 110
Cost of the gift
= 1.2 u + 1.8 u
= 3 u
= 3 x 110
= $330
Answer: $330
