Pierre and Sean had 90 staplers. After Pierre gave 18 staplers to Sean. Sean, in return, gave half of his staplers to Pierre. In the end, Pierre had twice as many staplers as Sean. How many staplers did Pierre have at first?
| |
Pierre |
Sean |
Total |
| Before |
1 u + 18 |
2 u - 18 |
90 |
| Change 1 |
- 18 |
+ 18 |
|
| After 1 |
1 u |
2 u |
|
| Change 2 |
+ 1 u |
- 1 u |
|
| After 2 |
2 u |
1 u |
90 |
Total number of staplers that Pierre and Sean had at first and in the end remains unchanged.
Total number of staplers
= 2 u + 1 u
= 3 u
1 u = 90 ÷ 3 = 30
Number of staplers that Pierre had at first
= 1 u + 18
= 30 + 18
= 48
Answer(s): 48
