## Elementary Statistics: A Step-by-Step Approach with Formula Card 9th Edition

a. $0.35$ b. $\mu=1.55$ $\sigma^2=1.81$ $\sigma=1.34$
a. What is the probability that an employee will get 2 or 3 applications during any given shift? Add up the corresponding probabilities: $p=0.20+0.15=0.35$ b. Find the mean, variance, and standard deviation for this probability distribution. Based on the definition and formula, mean=$\mu=\sum xP(x)=1.55$ variance=$\sigma^2=\sum (x-\mu)^2 P(x)=1.81$ standard deviation=$\sigma=\sqrt {\sigma^2}=1.34$