Ralph is 3 times as old as Sara. In 6 years, Ralph will be only twice as old as Sara will be then.
Find Ralph's age now.

R = 3SR + 6 = 2 (S+6)Substitute the first equation in the second one:(3S) + 6 = 2 (S + 6)3S + 6 = 2S + 12S + 6 = 12R = 18S = 6Check:R is 3 times S now.In 6 years, R will be (18 + 6) = 24, S will be (6 + 6) = 12.24 = 2 x 12        yay