Mary had $400 more than Roshel. Mary gave
35 of her money to Roshel. Roshel then gave 25% of her money to Mary. In the end, Mary had $138 less than Roshel. How much did Mary have at first?
| |
Mary |
Roshel |
| Comparing Mary and Roshel at first |
400 more |
|
| Before |
5 u |
+ 400 |
5 u |
|
| Change 1 |
- 3 u |
- 240 |
+ 3 u |
+ 240 |
| After 1 |
2 u |
+ 160 |
8 u |
+ 240 |
| Change 2 |
+ 2 u |
+ 60 |
- 2 u |
- 60 |
| After 2 |
4 u |
+ 220 |
6 u |
+ 180 |
35 x 400= 240
400 - 240 = 160
25% x 8 u
=
25100 x 8 u
= 2 u
25% x 240
=
25100 x 240
= 60
240 - 60 = 180
160 + 60 = 220
If Mary received another $138 in the end, Mary and Roshel would have the same amount of money.
6 u + 180 = 4 u + 220 + 138
6 u - 4 u = 220 + 138 - 180
2 u = 178
1 u = 178 ÷ 2 = 89
Amount that Mary had at first
= 5 u + 400
= 5 x 89 + 400
= 445 + 400
= $845
Answer(s): $845
