Pamela had 45 as many erasers as Min. The sum of the number of erasers Pamela and Min had was the same as the number of erasers that Barbara had. After trading, Barbara gave 20% of her erasers to Pamela and received 20% of Min's erasers. After that, Min continued to trade and increased her number of erasers in the end by 30%, find the ratio of her number of erasers to the sum of Pamela's and Barbara's erasers in the end.
| |
Pamela |
Barbara |
Min |
Total |
| Before |
4 u |
9 u |
5 u |
18 u |
| Change 1 |
+ 1.8 u |
- 1.8 u |
|
|
| Change 2 |
|
+ 1 u |
- 1 u |
|
| After 1 |
5.8 u |
8.2 u |
4 u |
|
| Change 3 |
- 1.2 u |
+ 1.2 u |
|
| After 2 |
12.8 u |
5.2 u |
18 u |
Total number of erasers that Pamela and Min had at first
= 4 u + 5 u
= 9 u
Number of erasers that Barbara had at first = 9 u
Number of erasers that Barbara gave to Pamela
= 20% x 9 u
=
20100 x 4 u
= 1.8 u
Number of erasers that Barbara received from Min
= 20% x 5 u
=
20100 x 5 u
= 1 u
Number of erasers that Min increased by when she continued to trade
= 30% x 4 u
=
30100 x 4 u
= 1.2 u
Number of erasers that Pamela and Barbara had in the end
= 5.8 u + 8.2 u - 1.2 u
= 12.8 u
In the end
Min : Pamela and Barbara
5.2 : 12.8
520 : 1280
13 : 32
Answer(s): 13 : 32
