Bobby had $670 more than Ethan at first. Bobby gave $90 to Ethan. As a result, Ethan has
29 as much money as Bobby. How much money had each of them at first?
- Bobby
- Ethan
| |
Bobby |
Ethan |
More |
| Before |
9 u + $90 |
2 u - $90 |
$670 |
| Change |
- $90 |
+ $90 |
|
| After |
9 u |
2 u |
|
(a)
Bobby had $670 more than Ethan at first. If Ethan received another $670, Bobby and Ethan would have the same amount at first.
9 u + 90 = 2 u - 90 + 670
9 u + 90 = 2 u + 580
9 u - 2 u = 580 - 90
7 u = 490
1 u = 490 ÷ 7 = 70
Amount that Bobby had at first
= 9 u + 90
= 9 x 70 + 90
= 630 + 90
= $720
(b)
Amount that Ethan had at first
= 2 u - 90
= 2 x 70 - 90
= 140 - 90
= $50
Answer(s): (a) $720; (b) $50
