Winnie went shopping with thrice as much money as Mary. After Winnie spent $770, Mary had four times as much money as Winnie had left. How much less money did Mary bring along for shopping than Winnie?
|
Winnie |
Mary |
Difference |
Before |
3x4 = 12 u |
1x4 = 4 u |
8 u |
Change |
- $770 |
|
|
After |
1 u |
4 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 4 is 4.
Amount that Winnie spent
= 12 u - 1 u
= 11 u
11 u = 770
1 u = 770 ÷ 11 = 70
Amount that Mary brought along less than Winnie
= 12 u - 4 u
= 8 u
= 8 x 70
= $560
Answer(s): $560