Brandon's and Erika's monthly allowances were the same at first. Brandon's allowance increased by 40% while Erika's increased by 20%. Given that Brandon's allowance would increase by another 10% if he had received $399 more from his mother, find the difference in the children's monthly allowances.
| |
Brandon |
Erika |
| Before |
1 u |
1 u |
| Change 1 |
+ 0.4 u |
+ 0.2 u |
| After 1 |
1.4 u |
1.2 u |
| Change 2 |
+ 0.14 u |
No change |
| After 2 |
1.54 u |
1.2 u |
Increase in Brandon's allowance
= 40% x 1 u
=
40100 x 1 u
= 0.4 u
Increase in Erika's allowance
= 20% x 1 u
=
20100 x 1 u
= 0.2 u
Increase in Brandon's allowance if his mother gave another $399
= 10% x 1.4 u
=
10100 x 1.4 u
= 0.14 u
0.14 u = 399
1 u = 399 ÷ 0.14 = 2850
Difference in the allowance between Brandon and Erika
= 1.4 u - 1.2 u
= 0.2 u
= 0.2 x 2850
= $570
Answer(s): $570
