Paul and Sam had some allowance in the ratio of 3 : 10. They shared some money to buy a necklace for their nephew. The ratio of the amount paid by Paul to the amount paid by Sam was 1 : 2. If Sam was left with $114 and Paul had spent
23 of his money, how much was the necklace they bought?
| |
Paul |
Sam |
| Before |
3 u |
10 u |
| Change |
- 2 u |
- 4 u |
Comparing the
amounts spent |
- 1x2 |
- 2x2 |
| After |
1 u |
114 |
The amount that Paul spent is repeated. Make the amount that Paul spent the same. LCM of 1 and 2 is 2.
Amount that Paul spent
=
23 x 3 u
= 2 u
Amount that Sam spent
= 2 x 2 u
= 4 u
Amount that Sam had left
= 10 u - 4 u
= 6 u
6 u = 114
1 u = 114 ÷ 6 = 19
Price of the necklace
= 2 u + 4 u
= 6 u
= 6 x 19
= $114
Answer(s): $114
