Yoko had $21 more than Tammy at first. After Yoko and Tammy spent an equal amount of money, Tammy had
310 as much as Yoko. How much money did Yoko have left?
| |
Yoko |
Tammy |
Difference |
| Before |
1 u + $21 |
1 u |
$21 |
| Change |
- 1 |
- 1 |
|
| After |
10 p |
3 p |
7 p |
Difference in the amounts between Yoko and Tammy
= 10 p - 3 p
= 7 p
Since both Yoko and Tammy spent an equal amount, the difference in the amounts that Yoko and Tammy had at first and in the end remains unchanged.
7 p = 21
1 p = 21 ÷ 7 = 3
Amount that Yoko had left
= 10 p
= 10 x 3
= $30
Answer(s): $30
