Riordan and Bobby had some allowance in the ratio of 5 : 8. They shared some money to buy a ring for their friend. The ratio of the amount paid by Riordan to the amount paid by Bobby was 1 : 2. If Bobby was left with $34 and Riordan had spent
35 of his money, how much was the ring they bought?
| |
Riordan |
Bobby |
| Before |
5 u |
8 u |
| Change |
- 3 u |
- 6 u |
Comparing the
amounts spent |
- 1x3 |
- 2x3 |
| After |
2 u |
34 |
The amount that Riordan spent is repeated. Make the amount that Riordan spent the same. LCM of 1 and 3 is 3.
Amount that Riordan spent
=
35 x 5 u
= 3 u
Amount that Bobby spent
= 2 x 3 u
= 6 u
Amount that Bobby had left
= 8 u - 6 u
= 2 u
2 u = 34
1 u = 34 ÷ 2 = 17
Price of the ring
= 3 u + 6 u
= 9 u
= 9 x 17
= $153
Answer(s): $153
