Two separate samples each with n 12 individuals receive two

Two separate samples, each with n = 12 individuals, receive two different treatments. After treatment the first sample has SS = 1740 and the second has SS = 1560. find pooled variance

s1^2 = SS/(n - 1) = 1740/(12 - 1) = 158.18 and
s2^2 = SS/(n - 1) = 1560/(12 - 1) = 141.82

Pooled s^2 = [{(n1 - 1) s1^2 + (n2 - 1) s2^2} / (n1 + n2 - 2)]
= [{(12 - 1) 158.18 + (12 - 1) 141.82} / (12 + 12 - 2)] = 150