# STAT

posted by
**Michelle** on
.

Determine the mean and standard deviation of the random variable for which the probability mass function is defined as follows:

P(X=x)= x-2/30 if x=3,12,21

posted by
**Michelle** on
.

Determine the mean and standard deviation of the random variable for which the probability mass function is defined as follows:

P(X=x)= x-2/30 if x=3,12,21