Oscar and Jack have some money. If Oscar gives $339 to Jack, the ratio of their money will be 2 : 5. If Oscar gives $486 to Jack, the ratio of their money will be 1: 4. How much does Oscar have?
| |
Case 1 |
Case 2 |
| |
Oscar |
Jack |
Oscar |
Jack |
| Before |
10 u + $339 |
25 u - $339 |
7 u + $486 |
28 u - $486 |
| Change |
- $339 |
+ $339 |
- $486 |
+ $486 |
After
|
2x5 =
10 u |
5x5 =
25 u |
1x7 =
7 u |
4x7 =
28 u |
The total amounts in both cases remain unchanged. Make the total amounts in both cases the same. LCM of 7 and 5 is 35.
The amount that Oscar has at first is the same in both cases.
10 u + 339 = 7 u + 486
10 u - 7 u = 486 - 339
3 u = 147
1 u = 147 ÷ 3 = 49
Amount that Oscar has
= 10 u + 339
= 10 x 49 + 339
= 490 + 339
= $829
Answer(s): $829
