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