Three girls, Xandra, Nicole and Shiyun had a total of 900 buttons. Some exchanges were made. First, Xandra gave Nicole as many buttons as Nicole had. After that, Nicole gave
14 of whatever she had then to Shiyun. Finally, Shiyun gave
15 of whatever she had to Xandra. As a result, they each had the same number of buttons. How many buttons did Xandra have at first?
| |
Xandra |
Nicole |
Shiyun |
Total |
| Before 1 |
? |
1 u |
|
900 |
| Change 1 |
- 1 u |
+ 1 u |
|
|
| After 1 |
|
2 u |
|
|
| Before 2 |
|
4 p |
|
900 |
| Change 2 |
|
- 1 p |
+ 1 p |
|
| After 2 |
|
3 p |
|
|
| Before 3 |
|
|
5 boxes |
900 |
| Change 3 |
+ 1 box |
|
- 1 box |
|
| After 3 |
|
|
4 boxes |
|
| After 3 |
1 group |
1 group |
1 group |
900 |
3 groups = 900
1 group = 900 ÷ 3 = 300
1 group = 4 boxes 4 boxes = 300
1 box = 300 ÷ 4 = 75
3 p = 1 group
1 p = 300 ÷ 3 = 100
4 p = 4 x 100 = 400
4 p = 2 u
2 u = 400
1 u = 400 ÷ 2 = 200
Number of buttons that Xandra had at first
= 1 group - 1 box + 1 u
= 300 - 75 + 200
= 425
Answer(s): 425
