Ken and Ethan were given some allowances each. If Ken spent $10 each day and Ethan spent $20 each day, Ken would still have $762 left when Ethan spent all his allowance. If Ken spent $20 each day and Ethan spent $10 each day, Ken would still have $72 left when Ethan spent all his allowance.
- How much allowance did Ken receive?
- How much allowance did Ethan receive?
|
Case 1 |
Case 2 |
|
Ken |
Ethan |
Ken |
Ethan |
Before |
1 u + 762 |
2 u |
2 p + 72 |
1 p |
Change |
- 1 u |
- 2 u |
- 2 p |
- 1 p |
After |
762 |
0 |
72 |
0 |
(a)
Simplify the ratio.
10 : 20 = 1 : 2
The allowance that Ethan had at first is the same for Case 1 and Case 2.
1 p = 2 u
2 p = 4 u
The allowance that Ken had at first is the same for Case 1 and Case 2.
4 u + 72 = 1 u + 762
4 u - 1 u = 762 - 72
3 u = 690
1 u = 690 ÷ 3 = 230
Allowance that Ken received
= 1 u + 762
= 230 + 762
= $992
(b)
Allowance that Ethan received
= 2 u
= 2 x 230
= $460
Answers: (a) $992; (b) $460