Mary had $30 more than Nora at first. After Mary and Nora spent an equal amount of money, Nora had
710 as much as Mary. How much money did Mary have left?
| |
Mary |
Nora |
Difference |
| Before |
1 u + $30 |
1 u |
$30 |
| Change |
- 1 |
- 1 |
|
| After |
10 p |
7 p |
3 p |
Difference in the amounts between Mary and Nora
= 10 p - 7 p
= 3 p
Since both Mary and Nora spent an equal amount, the difference in the amounts that Mary and Nora had at first and in the end remains unchanged.
3 p = 30
1 p = 30 ÷ 3 = 10
Amount that Mary had left
= 10 p
= 10 x 10
= $100
Answer(s): $100
