Nora went shopping with thrice as much money as Opal. After Nora spent $770, Opal had four times as much money as Nora had left. How much less money did Opal bring along for shopping than Nora?
| |
Nora |
Opal |
Difference |
| Before |
3x4 =
12 u |
1x4 =
4 u |
8 u |
| Change |
- $770 |
|
|
| After |
1 u |
4 u |
|
The amount that Opal has remains unchanged at first and in the end. Make the amount that Opal has the same. LCM of 1 and 4 is 4.
Amount that Nora spent
= 12 u - 1 u
= 11 u
11 u = 770
1 u = 770 ÷ 11 = 70
Amount that Opal brought along less than Nora
= 12 u - 4 u
= 8 u
= 8 x 70
= $560
Answer(s): $560
