Tommy had $138 and his brother had $29 at first. After they received an equal amount of allowance, Tommy had twice as much money as his brother. How much allowance did each of them receive?
| |
Tommy |
His brother |
Difference |
| Before |
$138 |
$29 |
$109 |
| Change |
+ ? |
+ ? |
|
| After |
2 u |
1 u |
1 u |
The difference in the amounts between Tommy and his brother at first and in the end remains unchanged after each received an equal amount of allowance.
Difference in the amounts between Perry and his brother
= 2 u - 1 u
= 1 u
1 u = 109
Allowance that each of them received
= 1 u - 29
= 109 - 29
= $80
Answer(s): $80
