Posted by
**manny** on
.

The probability that a person has immunity to a particular disease is 0.3. Find the mean and standard deviation for the random variable x, the number of people who have immunity in samples of size 28.

This is a binomial distribution.

mean= 28*.3

standard deviation= sqrt (28*.3(1-.3))

http://www.stat.yale.edu/Courses/1997-98/101/binom.htm

This is a binomial distribution.

mean= 28*.3

standard deviation= sqrt (28*.3(1-.3))

http://www.stat.yale.edu/Courses/1997-98/101/binom.htm

ok got it

thanks