Tammy went shopping with twice as much money as Tiffany. After Tammy spent $210, Tiffany had twice as much money as Tammy had left. How much less money did Tiffany bring along for shopping than Tammy?
| |
Tammy |
Tiffany |
Difference |
| Before |
2x2 =
4 u |
1x2 =
2 u |
2 u |
| Change |
- $210 |
|
|
| After |
1 u |
2 u |
|
The amount that Tiffany has remains unchanged at first and in the end. Make the amount that Tiffany has the same. LCM of 1 and 2 is 2.
Amount that Tammy spent
= 4 u - 1 u
= 3 u
3 u = 210
1 u = 210 ÷ 3 = 70
Amount that Tiffany brought along less than Tammy
= 4 u - 2 u
= 2 u
= 2 x 70
= $140
Answer(s): $140
