Info given:With a random sample of 9 men. let X denote the number of men with head circumference larger than 57.8cm. the normal mean=56cm and standard dev=1.8cm.

So this is a binomal dis-

they ask;
For X, calculate pr(X=2)?

second part,
Let X denote the number of men with HC larger than 57.8cm in a random sample of size 100. Use normal Aprrox to calculate Pr(X<20)?