Three girls, Tina, Yoko and Kathy had a total of 3060 stamps. Some exchanges were made. First, Tina gave Yoko as many stamps as Yoko had. After that, Yoko gave
13 of whatever she had then to Kathy. Finally, Kathy gave
15 of whatever she had to Tina. As a result, they each had the same number of stamps. How many stamps did Tina have at first?
|
Tina |
Yoko |
Kathy |
Total |
Before 1 |
? |
1 u |
|
3060 |
Change 1 |
- 1 u |
+ 1 u |
|
|
After 1 |
|
2 u |
|
|
Before 2 |
|
3 p |
|
3060 |
Change 2 |
|
- 1 p |
+ 1 p |
|
After 2 |
|
2 p |
|
|
Before 3 |
|
|
5 boxes |
3060 |
Change 3 |
+ 1 box |
|
- 1 box |
|
After 3 |
|
|
4 boxes |
|
After 3 |
1 group |
1 group |
1 group |
3060 |
3 groups = 3060
1 group = 3060 ÷ 3 = 1020
1 group = 4 boxes 4 boxes = 1020
1 box = 1020 ÷ 4 = 255
2 p = 1 group
1 p = 1020 ÷ 2 = 510
3 p = 3 x 510 = 1530
3 p = 2 u
2 u = 1530
1 u = 1530 ÷ 2 = 765
Number of stamps that Tina had at first
= 1 group - 1 box + 1 u
= 1020 - 255 + 765
= 1530
Answer(s): 1530