Answer:
The present age of Dave is 40 years
Explanation:
Let the present age of Johns be x
We are given that Dave is six years less then twice Johns age.
Dave's present age = 2x-6
We are also given that The sum of John and Dave's ages is 63.
So,
Dave's present age = 2x-6=2(23)-6=40
Hence The present age of Dave is 40 years