John and Archie had some allowance in the ratio of 5 : 9. They shared some money to buy a ring for their buddy. The ratio of the amount paid by John to the amount paid by Archie was 1 : 2. If Archie was left with $150 and John had spent
25 of his money, how much was the ring they bought?
| |
John |
Archie |
| Before |
5 u |
9 u |
| Change |
- 2 u |
- 4 u |
Comparing the
amounts spent |
- 1x2 |
- 2x2 |
| After |
3 u |
150 |
The amount that John spent is repeated. Make the amount that John spent the same. LCM of 1 and 2 is 2.
Amount that John spent
=
25 x 5 u
= 2 u
Amount that Archie spent
= 2 x 2 u
= 4 u
Amount that Archie had left
= 9 u - 4 u
= 5 u
5 u = 150
1 u = 150 ÷ 5 = 30
Price of the ring
= 2 u + 4 u
= 6 u
= 6 x 30
= $180
Answer(s): $180
