## Elementary Statistics (12th Edition)

p=0.2, q=0.8, $\mu=5$,$\sigma=2.$
1 out of 5 answers is correct, hence $p=\frac{1}{5}=0.2.$ q=1-p=1-0.2=0.8 mean of a binomial distribution: $\mu=n\cdotp=25\cdot0.2=5.$ standard deviation: $\sigma=\sqrt{n\cdot p\cdot q}=\sqrt{25 \cdot0.2\cdot0.8}=\sqrt4=2.$