(a). x is approx.. binomial because 1. Chance of five out of five remains the same 2. Sample consists of fixed no. Of observations. 3. Probability if the event if interest and not of interest is the same over all observations. 4. Each outcome is independent of the other.

(b) p= 0.5

(c) Using the binomial formula p= 0.03125

(d). using the binomial formula where n= 5 , x=0, and p= 0.5 you get

p (x>1) =. [ 1- ( 5!/0! 5! x 0.5^0 x 0.5^5 ) 1- .0315]

Part C asks for probability that exactly one of the five items is priced incur/rectly by the scanner.

Step 1. Probability of selecting one item incorrectly is 0.5.

Step 2. As you want to calculate probability exactly one out of five, use binomial formula for selection of one out of five which is: P ( X =1, n=5). = n! /x! ( n-x)! x [ p^x. (1-p) ^n-x]

Plug in x =1 , n=5 and p= 0.5 and you get. 5!/ 1! ( 5-1) ^ 1. (1-0.5) ^5-1