# MATHEMATICS

Question 17 It is known that 10% of the customers in an electronics store purchase an MP3 player. A random sample of 30 customers is selected. Assume that the customers’ purchases are made independently. In this binomial distribution application, which Excel statement will find the probability of 10 or fewer customers who purchase an MP3 player in this electronics store? =1- BINOMDIST(10,30,10%,TRUE) =1- BINOMDIST(10,30,10%,FALSE) =BINOMDIST(10,30,10%,TRUE) =BINOMDIST(10,30,10%,FALSE)

Question 18 A new surgical procedure is said to be successful 90% of the time. Suppose the procedure is performed five times. Assume that the results of each procedure are independent of one another. In this binomial distribution application, which Excel statement will find the probability of more than 2 successful surgical procedures? =BINOMDIST(2,5,90%,TRUE) =BINOMDIST(2,5,90%,FALSE) =1-BINOMDIST(2,5,90%,TRUE) =1-BINOMDIST(2,5,90%,FALSE)

Question 19 A new surgical procedure is said to be successful 90% of the time. Suppose the procedure is performed five times. Assume that the results of each procedure are independent of one another. In this binomial distribution application, which Excel statement will find the probability of between 2 and 4, inclusively, successful surgical procedures? =BINOMDIST(4,5,90%,FALSE)-BINOMDIST(2,5,90%,FALSE) =BINOMDIST(4,5,90%,TRUE)-BINOMDIST(1,5,90%,TRUE) =1-BINOMDIST(2,4,5,90%,TRUE) =1-BINOMDIST(2,4,5,90%,FALSE)

Question 20 Which of the following statement(s) is(are) a characteristic(s) of the normal distribution? • It is symmetric. • It has a bell shape. • The values of the mean, median, and mode are equal. All of the above are characteristics of a normal distribution. Only some of the above are characteristics of a normal distribution. None of the above are characteristics of a normal distribution. Question 21 Let μ = 160 and σ = 16. Find the z-score for the score, x = 150. -1.25 -0.625 0.675 0 Question 22 Let μ = 160 and σ = 16. Find the score x if the z-score = 1. 167 176 189 158 23 What proportion of the data from a normal distribution is within one standard deviation from the mean? 0.9544 0.6826 0.4772 0.5118 0.8733 24 The distribution of IQ scores for high school graduates is normally distributed with a mean of 105 and a standard deviation of 14. Identify the Excel statement that will find the probability that a person chosen at random from this group has an IQ score above 147. =1-NORMSDIST(147) =1-NORMSDIST(3) =NORMSDIST(3) =NORMSDIST(147) =1-NORMSDIST(105) 25 EPA studies of fuel consumption indicate compact car mileage to be normally distributed with a mean of 25.4 and a standard deviation of 6 mpg. Identify the Excel statement that will find the percentage of compact cars that get between 23 and 40 mpg. =[NORMSDIST(23)-NORMSDIST(40)]*100 =[1-NORMSDIST(23)-NORMSDIST(40)]*100 =[NORMSDIST(-0.4)+NORMSDIST(2.43)]*100 =[NORMSDIST(-0.4)-NORMSDIST(2.43)]*100 =[1-NORMSDIST(-0.4)-NORMSDIST(2.43)]*100 26 One year, the freshmen of all U.S. colleges had a mean average IQ of 107 and a standard deviation of 11. The IQ scores form a normal distribution. If a student is selected at random, find the probability that the student has an IQ below 100. Round your percentage to the hundredths 25.54% 26.23% 28.23% 30%