On Saturday, Tammy, Tiffany, Tina and Gillian spent a total of $206. On Sunday, Tammy spent twice of what she spent on Saturday, Tiffany spent the same as what she spent on Saturday, Tina spent $15 less than what she spent on Saturday, and Gillian spent $9 more than what she spent on Saturday. All of them spent an equal amount on Sunday. How much did Tammy and Gillian spend altogether on Saturday?
|
Tammy |
Tiffany |
Tina |
Gillian |
Total |
Before |
1 u |
3 u |
3 u + $15 |
3 u - $9 |
$206 |
Change |
x 3 |
|
- $15 |
+ $9 |
|
After |
3 u |
3 u |
3 u |
3 u |
|
Total amount that the four girls spent on Saturday
= 1 u + 3 u + 3 u + 15 + 3 u - 9
= 10 u + 15 - 9
= 10 u + 6
10 u + 6 = 206
10 u = 206 - 6
10 u = 200
1 u = 200 ÷ 10 = 20
Total amount that Tammy and Gillian spent on Saturday
= 1 u + 3 u - 9
= 4 u - 9
= 4 x 20 - 9
= 80 - 9
= $71
Answer(s): $71