sample Quiz #3 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Question 1-3 The following table contains the probability distribution for X = the number of weekly sales of a particular photocopying machine. X P(X) 0 1 2 3 0.05 0.1 0.15 0.2 4 0.5 1) Referring to the table, the probability of at most two machine being sold is __________. A) 0.70 B) 0.15 C) 0.30 D) 0.20 2) Referring to the table, the mean or expected value for the number of sales for a given week is __________. A) 3.0 B) 1.0 C) 2.0 D) 1.5 3) Referring to the table, the standard deviation of the number of sales is __________. A) 1.00 B) 1.23 C) 1.50 D) 3.0 4) The possible responses to the question "How long have you been living at your current residence?" are values from a __________ random variable. A) continuous B) discrete Questions 5-7 A survey indicates that for each trip to the supermarket, a shopper sends an average of 45 minutes with a standard deviation of 10 minutes. The length of time spent in the store is normally distributed. 5) Find the probability that a shopper will be in the store bewteen 24 and 54 minutes. A) 0.9000 B) 0.7980 C) 0.8159 D) -1.200 6) Find the probability that a shopper will be in the store less than 34.5 minutes A) -1.050 B) 0.3085 C) 0.6915 D) 0.1469 7) 69.15% of the shoppers will be in the store for more than how many minutes ? (hint: find X for the right-tail probability) A) 40.0 minutes B) 51.9 minutes C) 50.0 minutes D) 38.1 minutes Questions 8-9: From past records, a clothing store finds that 25% of the people who enter the store will make a purchase. During a one-hour period, 5 people enter the store. 8) The probability that at least two people will make a purchase is __________. A) 0.2637 B) 0.7627 C) 0.3672 D) 0.5786 9) The average number of people you should expect to make a purchase is __________. A) 1.50 B) 1.25 C) 0.25 D) 1.00 Answer Key Testname: SAMPLE_Q3_ANDERSON.TST MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) 2) 3) 4) 5) 6) 7) 8) 9) C A B A B D A C B