Assuming an Equal Chance of a New Baby Being a Boy

Multiple Choice

Assuming an equal chance of a new baby being a boy or a girl (that is, π = 0.5) , we would like to find the probability of 40 or more of the next 100 births at a local hospital will be boys. Using the normal approximation for binomial with a correction for continuity, we should use the z score ___.

A) 0.4
B) -2.1
C) 0.6
D) 2
E) -1.7