On Wednesday, Shannon, Joelle, Marion and Erika spent a total of $170. On Thursday, Shannon spent twice of what she spent on Wednesday, Joelle spent the same as what she spent on Wednesday, Marion spent $17 less than what she spent on Wednesday, and Erika spent $7 more than what she spent on Wednesday. All of them spent an equal amount on Thursday. How much did Shannon and Erika spend altogether on Wednesday?
|
Shannon |
Joelle |
Marion |
Erika |
Total |
Before |
1 u |
3 u |
3 u + $17 |
3 u - $7 |
$170 |
Change |
x 3 |
|
- $17 |
+ $7 |
|
After |
3 u |
3 u |
3 u |
3 u |
|
Total amount that the four girls spent on Wednesday
= 1 u + 3 u + 3 u + 17 + 3 u - 7
= 10 u + 17 - 7
= 10 u + 10
10 u + 10 = 170
10 u = 170 - 10
10 u = 160
1 u = 160 ÷ 10 = 16
Total amount that Shannon and Erika spent on Wednesday
= 1 u + 3 u - 7
= 4 u - 7
= 4 x 16 - 7
= 64 - 7
= $57
Answer(s): $57