Three girls, Gillian, Risa and Esther had a total of 3000 coins. Some exchanges were made. First, Gillian gave Risa as many coins as Risa had. After that, Risa gave
15 of whatever she had then to Esther. Finally, Esther gave
13 of whatever she had to Gillian. As a result, they each had the same number of coins. How many coins did Gillian have at first?
|
Gillian |
Risa |
Esther |
Total |
Before 1 |
? |
1 u |
|
3000 |
Change 1 |
- 1 u |
+ 1 u |
|
|
After 1 |
|
2 u |
|
|
Before 2 |
|
5 p |
|
3000 |
Change 2 |
|
- 1 p |
+ 1 p |
|
After 2 |
|
4 p |
|
|
Before 3 |
|
|
3 boxes |
3000 |
Change 3 |
+ 1 box |
|
- 1 box |
|
After 3 |
|
|
2 boxes |
|
After 3 |
1 group |
1 group |
1 group |
3000 |
3 groups = 3000
1 group = 3000 ÷ 3 = 1000
1 group = 2 boxes 2 boxes = 1000
1 box = 1000 ÷ 2 = 500
4 p = 1 group
1 p = 1000 ÷ 4 = 250
5 p = 5 x 250 = 1250
5 p = 2 u
2 u = 1250
1 u = 1250 ÷ 2 = 625
Number of coins that Gillian had at first
= 1 group - 1 box + 1 u
= 1000 - 500 + 625
= 1125
Answer(s): 1125