Assume that customers come into a store to either make a purchase or first. The
ID: 3150714 • Letter: A
Question
Assume that customers come into a store to either make a purchase or first. The retailer tracked 50 customers. It had been historically calculated that the proportion that bought was approximately 30% (0.3). This is the outcome of interest. Assume that you can life the Binomial approximation to the Normal distribution. Please consider continuity corrections. Given this information: a.) To pay a bonus, at least 20 customers should make a purchase. What is the probability that a bonus is paid out given 50 customers visiting the retailer?Explanation / Answer
a).
n=50
p=0.3
Expectation = np = 15
Variance = np(1 - p) = 10.5
Standard deviation = 3.2404
P( x at least 20 custemers)
With continuity correction, z value for 20,
Z=(19.5-15)/3.2404 =1.26
P( x 20) =P( z >1.26)
= 0.1038
b).
P( no more than 5 )
With continuity correction, z value for 5,
Z=(5.5-15)/3.2404 =-2.93
P( x 5) =P( z < -2.93)
= 0.0017