If Billy gives Penelope $5, he will have the same amount of money as her. If Penelope gives Billy $5, Billy will have five times as much money as her. How much money does Billy have?
|
Case 1 |
Case 2 |
|
Billy |
Penelope |
Billy |
Penelope |
Before |
3 u + 5 |
3 u - 5 |
1 u - 5 |
5 u + 5 |
Change |
- 5 |
+ 5 |
+ 5 |
- 5 |
After |
1x3 = 3 u |
1x3 = 3 u |
1x1 = 1 u |
5x1 = 5 u |
The total amount in both scenarios is the same. Make the total amount the same in bothe cases. LCM of 2 and 6 is 6.
In both case, Billy had the same amount at first.
3 u + 5 = 1 u - 5
3 u - 1 u = 5 + 5
2 u = 10
1 u = 10 ÷ 2 = 5
Amount that Billy has
= 3 u + 5
= 3 x 5 + 5
= $20
Answer(s): $20