Andy, Zeph and Paul had a total of 62 erasers. The ratio of the number of erasers that Zeph had to the number of erasers that Paul had was 8 : 5. After Andy and Zeph each gave away half of their erasers, the 3 children had 41 erasers left. How many erasers did Zeph and Paul have in the end?
| |
Andy |
Zeph |
Paul |
Total |
| Before |
2 p |
8 u |
5 u |
62 |
| Change |
- 1 p |
- 4 u |
|
- 21 |
| After |
1 p |
4 u |
5 u |
41 |
Total number of erasers that Andy and Zeph gave away
= 62 - 41
= 21
1 p + 4 u = 21 --- (1)
1 p + 4 u + 5 u = 41
1 p + 9 u = 41 --- (2)
(2) - (1)
(1 p + 9 u) - (1 p + 4 u) = 41 - 21
9 u - 4 u = 20
5 u = 20
1 u = 20 ÷ 5 = 4
Total number of erasers that Zeph and Paul had in the end
= 4 u + 5 u
= 9 u
= 9 x 4
= 36
Answer(s): 36
