Three girls, Fiona, Sarah and Vanessa had a total of 1800 stickers. Some exchanges were made. First, Fiona gave Sarah as many stickers as Sarah had. After that, Sarah gave
13 of whatever she had then to Vanessa. Finally, Vanessa gave
13 of whatever she had to Fiona. As a result, they each had the same number of stickers. How many stickers did Fiona have at first?
|
Fiona |
Sarah |
Vanessa |
Total |
Before 1 |
? |
1 u |
|
1800 |
Change 1 |
- 1 u |
+ 1 u |
|
|
After 1 |
|
2 u |
|
|
Before 2 |
|
3 p |
|
1800 |
Change 2 |
|
- 1 p |
+ 1 p |
|
After 2 |
|
2 p |
|
|
Before 3 |
|
|
3 boxes |
1800 |
Change 3 |
+ 1 box |
|
- 1 box |
|
After 3 |
|
|
2 boxes |
|
After 3 |
1 group |
1 group |
1 group |
1800 |
3 groups = 1800
1 group = 1800 ÷ 3 = 600
1 group = 2 boxes 2 boxes = 600
1 box = 600 ÷ 2 = 300
2 p = 1 group
1 p = 600 ÷ 2 = 300
3 p = 3 x 300 = 900
3 p = 2 u
2 u = 900
1 u = 900 ÷ 2 = 450
Number of stickers that Fiona had at first
= 1 group - 1 box + 1 u
= 600 - 300 + 450
= 750
Answer(s): 750