Let Wale's present age = x. Then Sonny's age = 2x Four years ago, Wale = x - 4 Sonny = 4(x - 4) = 2x - 4 \(4x - 16 = 2x - 4 \implies 4x - 2x = -4 + 16\) \(2x = 12 \implies x = 6\) Sonny = 2x = 2(6) = 12 years In z years' time, the sum of their ages = 66 Wale = 6 + z Sonny = 12 + z \(6 + z + 12 + z = 66 \implies 18 + 2z = 66\) \(2z = 66 - 18 = 48 \implies z = 24\) Therefore, in 24 years time, the sum of their ages will be 66.