Jeremy, Fred and Albert shared a bag of pens. Fred took 37 as many pens as Albert. Jeremy took twice as many pens as the total Fred and Albert took. After Jeremy had given 38 to Fred and 12 to Albert, Fred gave 3 to Albert. In the end, all three of them had the same number of pens. Find the difference between the number of pens that Jeremy and Fred had at first.
| |
Fred |
Albert |
Jeremy |
Total |
| Before |
3 u |
7 u |
20 u |
30 u |
| Change 1 |
+ 38 |
|
- 38 |
|
| Change 2 |
|
+ 12 |
- 12 |
|
| Change 3 |
- 3 |
+ 3 |
|
|
| After |
1x10 =
10 u |
1x10 =
10 u |
1x10 =
10 u |
3x10 =
30 u |
Total number of pens that Fred and Albert had at first
= 3 u + 7 u
= 10 u
Number of pens that Jeremy had at first
= 2 x 10 u
= 20 u
The total number of pens remains unchanged. Make the total number of pens the same. LCM of 3 and 30 is 30.
Number of pens that Albert received from Fred and Jeremy
= 10 u - 7 u
= 3 u
3 u = 12 + 3
3 u = 15
1 u = 15 ÷ 3 = 5
Difference between the number pens that Jeremy and Fred had at first
= 20 u - 3 u
= 17 u
= 17 x 5
= 85
Answer(s): 85
