Glen and Oliver shared some erasers in the ratio of 5 : 8. After both each gave away 42 erasers to their brother, the ratio of the number of erasers Glen had to the total number of erasers left was 1 : 4. How many erasers did the two boys have at first?
| |
Glen |
Oliver |
Difference |
| Before |
5x2 =
10 u |
8x2 =
16 u |
3x2 =
6 u |
| Change |
- 42 |
- 42 |
|
| After |
1x3 =
3 u |
3x3 =
9 u |
2x3 =
6 u |
Number of erasers that Glen and Oliver each gave to their brother is the same.
The difference in the number of erasers at first and in the end between Glen and Oliver remains unchanged. Make the difference in the number of erasers the same. LCM of 3 and 2 is 6.
Number of erasers that Glen gave to their brother
= 10 u - 3 u
= 7 u
7 u = 42
1 u = 42 ÷ 7 = 6
Number of erasers that the two boys had at first
= 10 u + 16 u
= 26 u
= 26 x 6
= 156
Answer(s): 156
