Archie and Tommy had some allowance in the ratio of 5 : 9. They shared some money to buy a ring for their mother. The ratio of the amount paid by Archie to the amount paid by Tommy was 1 : 3. If Tommy was left with $39 and Archie had spent
25 of his money, how much was the ring they bought?
| |
Archie |
Tommy |
| Before |
5 u |
9 u |
| Change |
- 2 u |
- 6 u |
Comparing the
amounts spent |
- 1x2 |
- 3x2 |
| After |
3 u |
39 |
The amount that Archie spent is repeated. Make the amount that Archie spent the same. LCM of 1 and 2 is 2.
Amount that Archie spent
=
25 x 5 u
= 2 u
Amount that Tommy spent
= 3 x 2 u
= 6 u
Amount that Tommy had left
= 9 u - 6 u
= 3 u
3 u = 39
1 u = 39 ÷ 3 = 13
Price of the ring
= 2 u + 6 u
= 8 u
= 8 x 13
= $104
Answer(s): $104
