Dylan and Oscar had 72 pens. After Dylan gave 10 pens to Oscar. Oscar, in return, gave half of his pens to Dylan. In the end, Dylan had twice as many pens as Oscar. How many pens did Dylan have at first?
| |
Dylan |
Oscar |
Total |
| Before |
1 u + 10 |
2 u - 10 |
72 |
| Change 1 |
- 10 |
+ 10 |
|
| After 1 |
1 u |
2 u |
|
| Change 2 |
+ 1 u |
- 1 u |
|
| After 2 |
2 u |
1 u |
72 |
Total number of pens that Dylan and Oscar had at first and in the end remains unchanged.
Total number of pens
= 2 u + 1 u
= 3 u
1 u = 72 ÷ 3 = 24
Number of pens that Dylan had at first
= 1 u + 10
= 24 + 10
= 34
Answer(s): 34
