Three girls, Min, Usha and Fanny had a total of 1980 marbles. Some exchanges were made. First, Min gave Usha as many marbles as Usha had. After that, Usha gave
13 of whatever she had then to Fanny. Finally, Fanny gave
14 of whatever she had to Min. As a result, they each had the same number of marbles. How many marbles did Min have at first?
|
Min |
Usha |
Fanny |
Total |
Before 1 |
? |
1 u |
|
1980 |
Change 1 |
- 1 u |
+ 1 u |
|
|
After 1 |
|
2 u |
|
|
Before 2 |
|
3 p |
|
1980 |
Change 2 |
|
- 1 p |
+ 1 p |
|
After 2 |
|
2 p |
|
|
Before 3 |
|
|
4 boxes |
1980 |
Change 3 |
+ 1 box |
|
- 1 box |
|
After 3 |
|
|
3 boxes |
|
After 3 |
1 group |
1 group |
1 group |
1980 |
3 groups = 1980
1 group = 1980 ÷ 3 = 660
1 group = 3 boxes 3 boxes = 660
1 box = 660 ÷ 3 = 220
2 p = 1 group
1 p = 660 ÷ 2 = 330
3 p = 3 x 330 = 990
3 p = 2 u
2 u = 990
1 u = 990 ÷ 2 = 495
Number of marbles that Min had at first
= 1 group - 1 box + 1 u
= 660 - 220 + 495
= 935
Answer(s): 935