Justin and Ethan were given some allowances each. If Justin spent $28 each day and Ethan spent $56 each day, Justin would still have $635 left when Ethan spent all his allowance. If Justin spent $56 each day and Ethan spent $28 each day, Justin would still have $47 left when Ethan spent all his allowance.
- How much allowance did Justin receive?
- How much allowance did Ethan receive?
|
Case 1 |
Case 2 |
|
Justin |
Ethan |
Justin |
Ethan |
Before |
1 u + 635 |
2 u |
2 p + 47 |
1 p |
Change |
- 1 u |
- 2 u |
- 2 p |
- 1 p |
After |
635 |
0 |
47 |
0 |
(a)
Simplify the ratio.
28 : 56 = 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 Justin had at first is the same for Case 1 and Case 2.
4 u + 47 = 1 u + 635
4 u - 1 u = 635 - 47
3 u = 588
1 u = 588 ÷ 3 = 196
Allowance that Justin received
= 1 u + 635
= 196 + 635
= $831
(b)
Allowance that Ethan received
= 2 u
= 2 x 196
= $392
Answers: (a) $831; (b) $392