statistics homework

Question

in a test of a gender-selection technique , results consisted of 208 baby girls and 204 baby boys. Based on this​ result, what is the probability of a girl born to a couple using this​ technique? Does it appear that the technique is effective in increasing the likelihood that a baby will be a​ girl?

what is the approximately the possibility for a girl to be born using this technique ?

Answer 1

P(girl) = (208/ (208 + 204)) = 0.505

It does not appear that 0.505 would be significantly different in a statistical sense from the expected 0.5 probability.

ho: p = 0.5

ha: p > 0.5

at alpha = 0.05, critical z value would be 1.96

z = 0.505 - 0.5 = 0.197

---------------

(0.5*0.5/412)^1/2

which is < 1.96, so would not reject ho.