Zoe and Roshel have some pencils in the ratio 5 : 11. Zoe has 72 less pencils than Roshel. How many pencils must Roshel give to Zoe so that they will have the same number of pencils?
| |
Zoe |
Roshel |
Total |
| Before |
5 u |
11 u |
16 u |
| Change |
+ 3 u |
- 3 u |
|
After |
1x8 =
8 u |
1x8 =
8 u |
2x8 =
16 u |
The total number of pencils remains unchanged. Make the total number of pencils at first and in the end the same. LCM of 2 and 16 is 16.
Difference in the number of pencils at first
= 11 u - 5 u
= 6 u
6 u = 72
1 u = 72 ÷ 6 = 12
Number of pencils that each of them had in the end
= 16 u ÷ 2
= 8 u
Number of pencils that Roshel must give to Zoe
= 8 u - 5 u
= 3 u
= 3 x 12
= 36
Answer(s): 36
