Question 1 The total area under the normal distribution curve is equal to 0.945 True False Question 2 Using the standard normal distribution, the Z-score representing the 90th percentile is 1.88. True False Question 3 0.2 pts 0.2 pts 0.2 pts A random variable X is normally distributed with a mean of 200 and a standard deviation of 25. Given that X = 150, its corresponding Z-score is -2.0 True False Question 4 0.25 pts If the value of the standard normal random variable Z is = 0, then the original score is where in relationship to the mean? To the right of the mean None of these choices To the left of the mean Equal to the mean Question 5 The standard deviation of a probability distribution is a measure of: the shape of the distribution skewness of the distribution variability of the distribution central location. Question 6 A manager of a popular retail store knows that the distribution of purchase amounts by its customers is approximately normal with a mean of $28 and a standard deviation of $9. a. What is the probability that a randomly selected customer will spend less than $15? [Select] b. What is the probability that a randomly selected customer will spend $20 or more? [Select] c. What is the probability that a randomly selected customer will spend $28 or more? [Select] 0.25 pts 1 pts Question 7 1 pts Wendy's fast-food restaurant sells hamburgers and chicken sandwiches. Suppose that on a typical weekday, the demand for hamburgers is normally distributed with a mean of 430 and standard deviation of 70 and the demand for chicken sandwiches is normally distributed with a mean of 150 and standard deviation of 30. Use this information to answer the following questions. a) How many chicken sandwiches must the restaurant stock to be 99% sure of not running out on a given day? [Select] b) If the restaurant stocks 530 hamburgers for a given day, what is the probability that it will run out of hamburgers that day? [Select] Question 8 0.9 pts A company sells printers with a mean life of 2 years (24 months) and a standard deviation of 5 months. The company will replace a printer if it is faulty within 16 months of sale. If they sell 10,000, how many can they expect to replace if life expectancy is normally distributed?