# Roll a Die question help please

#### Nasc0

if i roll a die 600 times. whats the mean and standard deviation of the number of 3's that show?

#### skeeter

MHF Helper
probability problems go in the statistics forum

#### Plato

MHF Helper
if i roll a die 600 times. whats the mean and standard deviation of the number of 3's that show?

If $$\displaystyle p$$ is the probability of success and $$\displaystyle N$$ is the number of trials then the mean is $$\displaystyle \mu=p\cdot N$$ and $$\displaystyle \sigma=\sqrt{Np(1-p)}$$.