Pierre had 60 more stamps than Mark. Pierre gave 25% of his stamps to Mark. Mark in return gave 60% of his stamps to Pierre. In the end, Mark had 200 less stamps than Pierre. How many stamps did Pierre have at first?
| |
Pierre |
Mark |
Comparing Pierre
and Peter at first |
60 more |
|
| Before |
4 u + 60 |
4 u |
| Change 1 |
- 1 u - 15 |
+ 1 u + 15 |
| After 1 |
3 u + 45 |
5 u + 15 |
| Change 2 |
+ 3 u + 9 |
- 3 u - 9 |
| After 2 |
6 u + 54 |
2 u + 6 |
25% =
25100 =
1425% x 60
=
25100 x 60
= 15
60% x 15
=
60100 x 15
= 9
60% x 5 u
=
60100 x 5 u
= 3 u
Mark had 200 less stamps than Pierre in the end. If another 200 stamps are given to Mark, both will have the same number of stamps.
6 u + 54 = 2 u + 6 + 200
6 u - 2 u = 6 + 200 - 54
4 u = 152
1 u = 152 ÷ 4 = 38
Number of Mark's stamps at first
= 4 u
= 4 x 38
= 152
Answer: 152
