Fred and Peter were given some allowances each. If Fred spent $10 each day and Peter spent $20 each day, Fred would still have $1117 left when Peter spent all his allowance. If Fred spent $20 each day and Peter spent $10 each day, Fred would still have $37 left when Peter spent all his allowance.
- How much allowance did Fred receive?
- How much allowance did Peter receive?
|
Case 1 |
Case 2 |
|
Fred |
Peter |
Fred |
Peter |
Before |
1 u + 1117 |
2 u |
2 p + 37 |
1 p |
Change |
- 1 u |
- 2 u |
- 2 p |
- 1 p |
After |
1117 |
0 |
37 |
0 |
(a)
Simplify the ratio.
10 : 20 = 1 : 2
The allowance that Peter had at first is the same for Case 1 and Case 2.
1 p = 2 u
2 p = 4 u
The allowance that Fred had at first is the same for Case 1 and Case 2.
4 u + 37 = 1 u + 1117
4 u - 1 u = 1117 - 37
3 u = 1080
1 u = 1080 ÷ 3 = 360
Allowance that Fred received
= 1 u + 1117
= 360 + 1117
= $1477
(b)
Allowance that Peter received
= 2 u
= 2 x 360
= $720
Answers: (a) $1477; (b) $720