x + (x + 2) + (x + 4) + (x + 6) = 3(x + 6)...combine like terms
4x + 12 = 3x + 18
4x - 3x = 18 - 12
x = 6
x + 2 = 6 + 2 = 8
x + 4 = 6 + 4 = 10
x + 6 = 6 + 6 = 12
so ur 4 numbers are : 6,8,10,and 12...and the sum of all of them (36) = 3 times the largest (3 x 12) = 36