Fred and Ivan were given some allowances each. If Fred spent $24 each day and Ivan spent $72 each day, Fred would still have $1368 left when Ivan spent all his allowance. If Fred spent $72 each day and Ivan spent $24 each day, Fred would still have $24 left when Ivan spent all his allowance.
- How much allowance did Fred receive?
- How much allowance did Ivan receive?
|
Case 1 |
Case 2 |
|
Fred |
Ivan |
Fred |
Ivan |
Before |
1 u + 1368 |
3 u |
3 p + 24 |
1 p |
Change |
- 1 u |
- 3 u |
- 3 p |
- 1 p |
After |
1368 |
0 |
24 |
0 |
(a)
Simplify the ratio.
24 : 72 = 1 : 3
The allowance that Ivan had at first is the same for Case 1 and Case 2.
1 p = 3 u
3 p = 9 u
The allowance that Fred had at first is the same for Case 1 and Case 2.
9 u + 24 = 1 u + 1368
9 u - 1 u = 1368 - 24
8 u = 1344
1 u = 1344 ÷ 8 = 168
Allowance that Fred received
= 1 u + 1368
= 168 + 1368
= $1536
(b)
Allowance that Ivan received
= 3 u
= 3 x 168
= $504
Answers: (a) $1536; (b) $504