Zeph had $77.90 more than David. After David had spent
79 of his money, Zeph had $172.40 more than David. How much money did Zeph have at first?
|
Zeph |
David |
More |
Before |
9 u + $77.90 |
9 u |
$77.90 |
Change |
|
- 7 u |
|
After |
9 u + $77.90 |
2 u |
7 u + $77.90 |
Zeph had $172.40 more than David in the end.
9 u + 77.90 - 2 u = 172.40
7 u + 77.90 = 172.40
7 u = 172.40 - 77.90
7 u = 94.50
1 u = 94.50 ÷ 7 = 13.50
Amount that Zeph had at first
= 9 u + 77.90
= 9 x 13.50 + 77.90
= 121.50 + 77.90
= $199.40
Answer(s): $199.40