Betty, Cathy and Barbara had a sum of money. The amount of money Betty had was
35 of the amount of money Cathy had. The ratio of the amount of money Cathy had to the total amount of money Barbara and Cathy had was 3: 8. After Barbara gave $65 to Cathy, she had as much money as Cathy. How much more money did Barbara have than Betty in the end?
Betty |
Cathy |
Barbara |
3x3 = 9 u |
5x3 = 15 u |
|
|
3x5 = 15 u |
5x5 = 25 u |
9 u |
15 u |
25 u |
The amount that Cathy had is the repeated identity. Make the amount that Cathy had the same. LCM of 5 and 3 is 15.
|
Betty |
Cathy |
Barbara |
Before |
9 u |
15 u |
25 u |
Change |
No change |
+ 65 |
- 65 |
After |
9 u |
15 u + 65 |
25 u - 65 |
The amount that Barbara and Cathy had in the end is the same.
25 u - 65 = 15 u + 65
25 u - 15 u = 65 + 65
10 u = 130
1 u = 130 ÷ 10 = 13
Amount that Barbara had more than Betty in the end
= 25 u - 65 - 9 u
= 16 u - 65
= 16 x 13 - 65
= 208 - 65
= $143
Answer(s): $143