BANA 2372 Exam 2 Questions with Correct Answers

BANA 2372 Exam 2 Questions with Correct Answers Forty percent of all registered voters in a national election are female. A random sample of 5 voters is selected. Refer to Exhibit 5-9. The probability that there are no females in the sample is . - Answer-.0778 For a uniform probability density function, the height of the function . - Answer-is the same for each value of x The student body of a large university consists of 60% female students. A random sample of 8 students is selected. Refer to Exhibit 5-8. What is the probability that among the students in the sample at least 7 are female? - Answer-.1064 For a standard normal distribution, the probability of obtaining a z value between -1.9 and 1.7 is . - Answer-.9267 Probability Distribution x f(x) 10 .2 20 .3 30 .4 40 .1 Refer to Exhibit 5-6. The expected value of x equals . - Answer-24 AMR is a computer-consulting firm. The number of new clients that it has obtained each month has ranged from 0 to 6. The number of new clients has the probability distribution that is shown below. Number of New Clients Probability 0 .05 1 .10 2 .15 3 .35 4 .20 5 .10 6 .05 Refer to Exhibit 5-5. The standard deviation is . - Answer-3.05 Assume z is a standard normal random variable. Then P(z ≥ 2.11) equals . - Answer-.0174 For a standard normal distribution, the probability of obtaining a z value of less than 1.6 is . - Answer-.9452 Assume that you have a binomial experiment with p = 0.5 and a sample size of 100. The expected value of this distribution is . - Answer-50 A standard normal distribution is a normal distribution with . - Answer-a mean of 0 and a standard deviation of 1 The life expectancy of a particular brand of tire is normally distributed with a mean of 40,000 and a standard deviation of 5,000 miles. Refer to Exhibit 6-6. What percentage of tires will have a life of 34,000 to 46,000 miles? - Answer-76.98% A property of the Poisson distribution is that the mean equals the . - Answer- variance Excel's NORM.INV function can be used to compute - Answer-cumulative probabilities for a normally distributed x value Excel's BINOM.DIST function can be used to compute . - Answer-both binomial probabilities and cumulative binomial probabilities The ages of students at a university are normally distributed with a mean of 21. What percentage of the student body is at least 21 years old? - Answer-50% In the textile industry, a manufacturer is interested in the number of blemishes or flaws occurring in each 100 feet of material. The probability distribution that has the greatest chance of applying to this situation is the . - Answer-Poisson distribution The weight of items produced by a machine is normally distributed with a mean of 8 ounces and a standard deviation of 2 ounces. Refer to Exhibit 6-5. What is the probability that a randomly selected item weighs exactly 8 ounces? - Answer-None of the answers is correct. Assume that you have a binomial experiment with p = 0.4 and a sample size of 50. The variance of this distribution is . - Answer-12 The number of customers who enter a store during one day is an example of - Answer-a discrete random variable For the standard normal probability distribution, the area to the left of the mean is - Answer-0.5 Larger values of the standard deviation result in a normal curve that is . - Answer- wider and flatter