Question 939639
Let the age of brad be br and age of ben be b
From the first statement, br = 2*b + 9  ------ eqn 1
From the second statement, i.e in 15 yrs,
Brad's age in 15yrs is br+15 and Ben's age would be b+15
Given that the sum of their ages would be 111
i.e br+15+b+15 = 111
Simplifying
br+b = 111-30
br+b =81 --------eqn 2
Substituting 1 into 2,
2*b + 9 + b =81,
3b = 81-9 = 72
b = 72/3 = 24
Therefore Ben's age, b is 24 years
QED



Also we can find br, i.e br = 2*b+9 = 2*24+9 = 57
Therefore, Brad's age is also 57
In the next 15 years, their age sum would absolutely be 111