Question

for classes of 279 students, find the mean and standard deviation for the number born on 4th of July. ignore leap year

Answer 1

The probability of any student being born on 4th of July is 1/365. The binomial distribution applies therefore:
\[mean=np=279\times \frac{1}{365}=you\ can\ calculate\]
\[standard\ deviation=\sqrt{np(1-p})=\sqrt{279\times\frac{1}{365}\times\frac{364}{365}}\]