Question

Independent samples of n1 = 400 and n2= 400 observations were selected from binomial populations 1 and 2, and x1 = 100 and x2 = 127 successes were observed. Calculate the approximate standard error for the statistic, the point estimator for the difference ( p1-p2) in the two binomial proportions?
A. 0.0441
B. 0.0287
C. 0.0536
D. 0.0318