Luis's and Abi's monthly allowances were the same at first. Luis's allowance increased by 50% while Abi's decreased by 10%. Given that Luis's allowance would decrease by another 40% if he had received $1200 less from his parents, find the difference in the children's monthly allowances.
| |
Luis |
Abi |
| Before |
1 u |
1 u |
| Change 1 |
+ 0.5 u |
- 0.1 u |
| After 1 |
1.5 u |
0.9 u |
| Change 2 |
- 0.6 u |
No change |
| After 2 |
0.9 u |
0.9 u |
Increase in Luis's allowance
= 50% x 1 u
=
50100 x 1 u
= 0.5 u
Decrease in Abi's allowance
= 10% x 1 u
=
10100 x 1 u
= 0.1 u
Decrease in Luis's allowance if he had received $1200 less from his parents
= 40% x 1.5 u
=
40100 x 1.5 u
= 0.6 u
0.6 u = 1200
1 u = 1200 ÷ 0.6 = 2000
Difference in the allowance between Luis and Abi
= 1.5 u - 0.9 u
= 0.6 u
= 0.6 x 2000
= $1200
Answer(s): $1200
