Tammy went shopping with thrice as much money as Gem. After Tammy spent $400, Gem had twice as much money as Tammy had left. How much less money did Gem bring along for shopping than Tammy?
| |
Tammy |
Gem |
Difference |
| Before |
3x2 =
6 u |
1x2 =
2 u |
4 u |
| Change |
- $400 |
|
|
| After |
1 u |
2 u |
|
The amount that Gem has remains unchanged at first and in the end. Make the amount that Gem has the same. LCM of 1 and 2 is 2.
Amount that Tammy spent
= 6 u - 1 u
= 5 u
5 u = 400
1 u = 400 ÷ 5 = 80
Amount that Gem brought along less than Tammy
= 6 u - 2 u
= 4 u
= 4 x 80
= $320
Answer(s): $320
