Bobby had $110 less than Perry. If Perry spends $130 and Bobby's mother gave Bobby $570, Perry will have
14 as much money as Bobby. How much money did Bobby and Perry have?
| |
Make p the same
(1)x4 = (3) |
Bobby
(1) |
Perry
(2) |
| Before |
4 u |
1 u |
1 u + 110 |
| Change |
- 520 |
- 130 |
+ 570 |
| After |
4 p |
1 p |
4 p |
Since Bobby had $110 less than Perry, this means Perry had $110 more than Bobby.
1 u - 130 = 1 p --- (1)
1 u + 110 + 570 = 4 p
1 u + 680 =
4 p --- (2)
Make p the same.
(1)
x4
4 u - 520 =
4 p --- (3)
(3) = (2)
4 u - 520 = 1 u + 680
4 u - 1 u = 680 + 520
3 u = 1200
1 u = 1200 ÷ 3 = 400
Total amount that Bobby and Perry had
= 1 u + 1 u + 110
= 2 u + 110
= 2 x 400 + 110
= 800 + 110
= $910
Answer(s): $910
