Pierre, David and Ben shared a bag of stamps. David took 27 as many stamps as Ben. Pierre took four times as many stamps as the total David and Ben took. After Pierre had given 34 to David and 8 to Ben, David gave 8 to Ben. In the end, all three of them had the same number of stamps. Find the difference between the number of stamps that Pierre and David had at first.
| |
David |
Ben |
Pierre |
Total |
| Before |
2 u |
7 u |
36 u |
45 u |
| Change 1 |
+ 34 |
|
- 34 |
|
| Change 2 |
|
+ 8 |
- 8 |
|
| Change 3 |
- 8 |
+ 8 |
|
|
| After |
1x15 =
15 u |
1x15 =
15 u |
1x15 =
15 u |
3x15 =
45 u |
Total number of stamps that David and Ben had at first
= 2 u + 7 u
= 15 u
Number of stamps that Pierre had at first
= 4 x 15 u
= 36 u
The total number of stamps remains unchanged. Make the total number of stamps the same. LCM of 3 and 45 is 45.
Number of stamps that Ben received from David and Pierre
= 15 u - 7 u
= 8 u
8 u = 8 + 8
8 u = 16
1 u = 16 ÷ 8 = 2
Difference between the number stamps that Pierre and David had at first
= 36 u - 2 u
= 34 u
= 34 x 2
= 68
Answer(s): 68
