The ratio of the amount of money that Julie and Diana brought along was 3 : 4. For their sister's present, Julie and Diana shared the cost in the ratio of 2 : 3. Julie used up
25 of her money to pay for her share. After paying for her share, Diana had $121 left. How much was the present?
| |
Julie |
Diana |
| Before |
3 u |
4 u |
| Change |
- 1.2 u |
- 1.8 u |
Comparing the cost shared
between Julie and Diana |
- 2 p =
- 1.2 u |
- 3 p =
- 1.8 u |
| After |
1.8 u |
121 |
Amount that Julie 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 Diana had left
= 4 u - 1.8 u
= 2.2 u
2.2 u = 121
1 u = 121 ÷ 2.2 = 55
Cost of the present
= 1.2 u + 1.8 u
= 3 u
= 3 x 55
= $165
Answer: $165
