Pamela, Shiyun and Mary had a sum of money. The amount of money Pamela had was
23 of the amount of money Shiyun had. The ratio of the amount of money Shiyun had to the total amount of money Mary and Shiyun had was 2: 5. After Mary gave $69 to Shiyun, she had as much money as Shiyun. How much more money did Mary have than Pamela in the end?
Pamela |
Shiyun |
Mary |
2x2 = 4 u |
3x2 = 6 u |
|
|
2x3 = 6 u |
3x3 = 9 u |
4 u |
6 u |
9 u |
The amount that Shiyun had is the repeated identity. Make the amount that Shiyun had the same. LCM of 3 and 2 is 6.
|
Pamela |
Shiyun |
Mary |
Before |
4 u |
6 u |
9 u |
Change |
No change |
+ 69 |
- 69 |
After |
4 u |
6 u + 69 |
9 u - 69 |
The amount that Mary and Shiyun had in the end is the same.
9 u - 69 = 6 u + 69
9 u - 6 u = 69 + 69
3 u = 138
1 u = 138 ÷ 3 = 46
Amount that Mary had more than Pamela in the end
= 9 u - 69 - 4 u
= 5 u - 69
= 5 x 46 - 69
= 230 - 69
= $161
Answer(s): $161