Liam and Perry had 51 pens. After Liam gave 19 pens to Perry. Perry, in return, gave half of his pens to Liam. In the end, Liam had twice as many pens as Perry. How many pens did Liam have at first?
| |
Liam |
Perry |
Total |
| Before |
1 u + 19 |
2 u - 19 |
51 |
| Change 1 |
- 19 |
+ 19 |
|
| After 1 |
1 u |
2 u |
|
| Change 2 |
+ 1 u |
- 1 u |
|
| After 2 |
2 u |
1 u |
51 |
Total number of pens that Liam and Perry had at first and in the end remains unchanged.
Total number of pens
= 2 u + 1 u
= 3 u
1 u = 51 ÷ 3 = 17
Number of pens that Liam had at first
= 1 u + 19
= 17 + 19
= 36
Answer(s): 36
