Risa had $450 more than Betty. Risa gave
23 of her money to Betty. Betty then gave 20% of her money to Risa. In the end, Risa had $246 less than Betty. How much did Risa have at first?
|
Risa |
Betty |
Comparing Risa and Betty at first |
450 more |
|
Before |
3 u |
+ 450 |
3 u |
|
Change 1 |
- 2 u |
- 300 |
+ 2 u |
+ 300 |
After 1 |
1 u |
+ 150 |
5 u |
+ 300 |
Change 2 |
+ 1 u |
+ 60 |
- 1 u |
- 60 |
After 2 |
2 u |
+ 210 |
4 u |
+ 240 |
23 x 450= 300
450 - 300 = 150
20% x 5 u
=
20100 x 5 u
= 1 u
20% x 300
=
20100 x 300
= 60
300 - 60 = 240
150 + 60 = 210
If Risa received another $246 in the end, Risa and Betty would have the same amount of money.
4 u + 240 = 2 u + 210 + 246
4 u - 2 u = 210 + 246 - 240
2 u = 216
1 u = 216 ÷ 2 = 108
Amount that Risa had at first
= 3 u + 450
= 3 x 108 + 450
= 324 + 450
= $774
Answer(s): $774