Three girls, Jaslyn, Gem and Wendy had a total of 1200 pens. Some exchanges were made. First, Jaslyn gave Gem as many pens as Gem had. After that, Gem gave
13 of whatever she had then to Wendy. Finally, Wendy gave
13 of whatever she had to Jaslyn. As a result, they each had the same number of pens. How many pens did Jaslyn have at first?
|
Jaslyn |
Gem |
Wendy |
Total |
Before 1 |
? |
1 u |
|
1200 |
Change 1 |
- 1 u |
+ 1 u |
|
|
After 1 |
|
2 u |
|
|
Before 2 |
|
3 p |
|
1200 |
Change 2 |
|
- 1 p |
+ 1 p |
|
After 2 |
|
2 p |
|
|
Before 3 |
|
|
3 boxes |
1200 |
Change 3 |
+ 1 box |
|
- 1 box |
|
After 3 |
|
|
2 boxes |
|
After 3 |
1 group |
1 group |
1 group |
1200 |
3 groups = 1200
1 group = 1200 ÷ 3 = 400
1 group = 2 boxes 2 boxes = 400
1 box = 400 ÷ 2 = 200
2 p = 1 group
1 p = 400 ÷ 2 = 200
3 p = 3 x 200 = 600
3 p = 2 u
2 u = 600
1 u = 600 ÷ 2 = 300
Number of pens that Jaslyn had at first
= 1 group - 1 box + 1 u
= 400 - 200 + 300
= 500
Answer(s): 500