Shannon went shopping with twice as much money as Mary. After Shannon spent $400, Mary had thrice as much money as Shannon had left. How much less money did Mary bring along for shopping than Shannon?
| |
Shannon |
Mary |
Difference |
| Before |
2x3 =
6 u |
1x3 =
3 u |
3 u |
| Change |
- $400 |
|
|
| After |
1 u |
3 u |
|
The amount that Mary has remains unchanged at first and in the end. Make the amount that Mary has the same. LCM of 1 and 3 is 3.
Amount that Shannon spent
= 6 u - 1 u
= 5 u
5 u = 400
1 u = 400 ÷ 5 = 80
Amount that Mary brought along less than Shannon
= 6 u - 3 u
= 3 u
= 3 x 80
= $240
Answer(s): $240
