Answer: The youngest age Warren can be of 3 years.
Explanation:
Let x = Age of Warren
As per given,
Age of Marty = 4x-2
Also, sum of their ages is greater than 10.
i.e. (Age of Warren) + ( Age of Marty) >10
Since 3 is just greater than 2.4.
So, the youngest age Warren can be of 3 years.