The ratio of the amount of money that Emma and Risa brought along was 4 : 5. For their brother's present, Emma and Risa shared the cost in the ratio of 2 : 3. Emma used up
25 of her money to pay for her share. After paying for her share, Risa had $195 left. How much was the present?
| |
Emma |
Risa |
| Before |
4 u |
5 u |
| Change |
- 1.6 u |
- 2.4 u |
Comparing the cost shared
between Emma and Risa |
- 2 p =
- 1.6 u |
- 3 p =
- 2.4 u |
| After |
2.4 u |
195 |
Amount that Emma spent on the present
=
25 x 4 u
= 1.6 u
2 p = 1.6 u
1 p = 1.6 u ÷ 2 = 0.8
3 p = 3 x 0.8 = 2.4 u
Amount that Risa had left
= 5 u - 2.4 u
= 2.6 u
2.6 u = 195
1 u = 195 ÷ 2.6 = 75
Cost of the present
= 1.6 u + 2.4 u
= 4 u
= 4 x 75
= $300
Answer: $300
