2. 120 points About 35% of all small businesses in the United States have websit
ID: 3318162 • Letter: 2
Question
2. 120 points About 35% of all small businesses in the United States have website. You randomly select 20 small businesses. Answer the following questions by stating any assumptions you make a How many of them you expect to have a website? b. What is the probability that there are at most three of them have a website? 3. 120 points] Spose that crowd size at home games for a particular football club follows a normal distribution with mean 26, 000 and standard deviation 5,000 a. What is the probability that of crowds are less than 30, 000? b. Calculate the 90h percentile of the capacity of the crowd for the home games.Explanation / Answer
2. Assuming the surveys are independent and probability is constant,
This is binomial distribution
n = 20
p = 0.35
q = 1 - p = 0.65
a) Expected number of businesses to have website = np
= 0.35 x 20 = 7
b) P(at most 3 of them have a website) = P(0) + P(1) + P(2) + P(3)
= 0.6520 + 20x0.35x0.6519 + 20C2x0.352x0.6518 + 20C3x0.353x0.6517
= 0.0002 + 0.0020 + 0.0100 + 0.0323
= 0.0445
P.S: Please post different questions separately
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.