Paul, Liam and Ivan had some erasers in the ratio of 2 : 3 : 5. Ivan gave 40% of his erasers to Paul and Liam. As a result, Paul had the same number of erasers as Liam and Ivan had 48 fewer erasers than Paul.
- What was the percentage increase in Paul's erasers after receiving from Ivan?
- How many erasers did Liam have at first?
Paul |
Liam |
Ivan |
Total |
2 u |
3 u |
5 u |
10 u |
+ 2 u |
- 2 u |
|
3.5 u |
3.5 u |
3 u |
10 u |
(a)
Number of erasers that Ivan gave away
= 40% x 5
=
40100 x 5
= 2 u
Number of erasers that Paul and Liam each had in the end
= (10 u - 3 u) ÷ 2
= 7 u ÷ 2
= 3.5 u
Increase in the number of erasers that Paul had
= 3.5 u - 2 u
= 1.5 u
Percentage increase in Paul's erasers after receiving from Ivan
=
1.52 x 100%
= 75%
(b)
3.5 u = 3 u + 48
3.5 u - 3 u = 48
0.5 u = 48
1 u = 48 ÷ 0.5 = 96
Number of erasers that Liam had at first
= 3 u
= 3 x 96
= 288
Answer(s): (a) 75%; (b) 288