Set up the problem as an equation where X is years: 14+X = (56+X)/2 Solve for X 14+X = 28 + 0.5*(X) subtract 14 from both sides: X = 14 + 0.5*(X) subtract 0.5*(X) from both sides: 0.5*(X) = 14 Solve for X by dividing both sides by 0.5: X = 28
So the answer is a) 28
