Sam's and Gabby's monthly allowances were the same at first. Sam's allowance increased by 25% while Gabby's decreased by 15%. Given that Sam's allowance would decrease by another 40% if he had received $760 less from his fathers, find the difference in the children's monthly allowances.
|
Sam |
Gabby |
Before |
1 u |
1 u |
Change 1 |
+ 0.25 u |
- 0.15 u |
After 1 |
1.25 u |
0.85 u |
Change 2 |
- 0.5 u |
No change |
After 2 |
0.75 u |
0.85 u |
Increase in Sam's allowance
= 25% x 1 u
=
25100 x 1 u
= 0.25 u
Decrease in Gabby's allowance
= 15% x 1 u
=
15100 x 1 u
= 0.15 u
Decrease in Sam's allowance if he had received $760 less from his fathers
= 40% x 1.25 u
=
40100 x 1.25 u
= 0.5 u
0.5 u = 760
1 u = 760 ÷ 0.5 = 1520
Difference in the allowance between Sam and Gabby
= 1.25 u - 0.85 u
= 0.4 u
= 0.4 x 1520
= $608
Answer(s): $608