Xuan and Tiffany had equal amount of money. Each day, Xuan spent $17 and Tiffany spent $23. When Xuan had $90 left, Tiffany had
15 as much money left as Xuan. How much money did the two girls have at first?
| |
Xuan |
Tiffany |
| Before |
17 u + 90 |
23 u + 18 |
| Change |
- 17 u |
- 23 u |
| After |
$90 |
$18 |
Amount that Tiffany had left
=
15 x 90
= $18
The amount that Xuan and Tiffany had at first is the same.
23 u + 18 = 17 u + 90
23 u - 17 u = 90 - 18
6 u = 72
1 u = 72 ÷ 6 = 12
Amount that Xuan had at first
= 17 u + 90
= 17 x 12 + 90
= 204 + 90
= $294
Total amount that both girls had at first
= 2 x 294
= $588
Answer(s): $588
