Three girls, Sabrina, Kylie and Xuan had a total of 1170 buttons. Some exchanges were made. First, Sabrina gave Kylie as many buttons as Kylie had. After that, Kylie gave
14 of whatever she had then to Xuan. Finally, Xuan gave
14 of whatever she had to Sabrina. As a result, they each had the same number of buttons. How many buttons did Sabrina have at first?
|
Sabrina |
Kylie |
Xuan |
Total |
Before 1 |
? |
1 u |
|
1170 |
Change 1 |
- 1 u |
+ 1 u |
|
|
After 1 |
|
2 u |
|
|
Before 2 |
|
4 p |
|
1170 |
Change 2 |
|
- 1 p |
+ 1 p |
|
After 2 |
|
3 p |
|
|
Before 3 |
|
|
4 boxes |
1170 |
Change 3 |
+ 1 box |
|
- 1 box |
|
After 3 |
|
|
3 boxes |
|
After 3 |
1 group |
1 group |
1 group |
1170 |
3 groups = 1170
1 group = 1170 ÷ 3 = 390
1 group = 3 boxes 3 boxes = 390
1 box = 390 ÷ 3 = 130
3 p = 1 group
1 p = 390 ÷ 3 = 130
4 p = 4 x 130 = 520
4 p = 2 u
2 u = 520
1 u = 520 ÷ 2 = 260
Number of buttons that Sabrina had at first
= 1 group - 1 box + 1 u
= 390 - 130 + 260
= 520
Answer(s): 520