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