What are the mean and standard deviation of a binomial probability distribution with #n=12 # and #p=7/60 #?

1 Answer
Mar 4, 2016

Mean is #1.4# and Standard Deviation is #1.112#

Explanation:

The mean and standard deviation of a binomial probability distribution are #np# and #sqrt(npq)# respectively where #n# is number of tria;ls and #p# is probability of success of the event. Here #q=1-p#, and is the probability of failure of the event.

With #n=12# and #p=7/60#, #q=1-7/60=53/60#.

Hence mean is #12xx7/60=7/5=1.4# and

Standard Deviation is #sqrt(12xx7/60xx53/60)=(1/60)sqrt(7xx12xx53)#

= #sqrt4452/60=66.7233/60=1.112#