Practice Final part 2 Math 160 MULTIPLE CHOICE. Choose the ...

1 Practice Final part 2 Math 160 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the an appropriate ) State whether the variable is discrete or height of a player on a basketball teamA) discreteB) continuous1)2) State whether the variable is discrete or cost of a Statistics textbookA) discreteB) continuous2)3) The random variable x represents the number of cars per household in a town of 1000 the probability of randomly selecting a household that has less than two Households0125142822563108 4 83A) ) ) ) )4) The random variable x represents the number of credit cards that adults have along with thecorresponding probabilities. Find the mean and standard deviation. x P(x)0 4 ) mean: ; standard deviation: ) mean: ; standard deviation: ) mean: ; standard deviation: ) mean: ; standard deviation: )5) A test consists of 90 MULTIPLE choice questions, each with five possible answers, only one of whichis correct.

2 Find the mean and the standard deviation of the number of correct ) mean: 45; standard deviation: ) mean: 18; standard deviation: ) mean: 18; standard deviation: ) mean: 45; standard deviation: )6) A test consists of 10 MULTIPLE choice questions, each with five possible answers, one of which iscorrect. To pass the test a student must get 60% or better on the test. If a student randomly guesses,what is the probability that the student will pass the test?A) ) ) ) )7) Assume that male and female births are equally likely and that the birth of any child does notaffect the probability of the gender of any other children. Find the probability of at most three boysin ten ) ) ) ) )18) Find the area under the standard normal curve to the right of z = ) ) ) ) )Provide an appropriate response. Use the Standard Normal Table to find the ) The lengths of pregnancies of humans are normally distributed with a mean of 268 days and astandard deviation of 15 days.

3 Find the probability of a pregnancy lasting less than 250 ) ) ) ) )10) The distribution of cholesterol levels in teenage boys is approximately normal with = 170 and = 30 (Source: National Center for Health Statistics). Levels above 200 warrant attention. Findthe probability that a teenage boy has a cholesterol level greater than ) ) ) ) )Provide an appropriate ) Compare the scores: a score of 220 on a test with a mean of 200 and a standard deviation of 21 anda score of 90 on a test with a mean of 80 and a standard deviation of ) A score of 90 with a mean of 80 and a standard deviation of 8 is ) You cannot determine which score is better from the given ) A score of 220 with a mean of 200 and a standard deviation of 21 is ) The two scores are statistically the )12) Assume that the heights of women are normally distributed with a mean of and astandard deviation of inches.

4 Find Q3, the third quartile that separates the bottom 75% from thetop 25%.A) ) ) ) )13) Assume that the heights of women are normally distributed with a mean of inches and astandard deviation of inches. If 100 women are randomly selected, find the probability thatthey have a mean height greater than ) ) ) ) )14) The lengths of pregnancies are normally distributed with a mean of 268 days and a standarddeviation of 15 days. If 64 women are randomly selected, find the probability that they have amean pregnancy between 266 days and 268 ) ) ) ) )15) A random sample of 120 students has a test score average Assume a population standarddeviation of Find the margin of error if c = ) ) ) ) )16) Find the critical value zc that corresponds to a 94% confidence ) ) ) ) )17) A random sample of 40 students has a mean annual earnings of $ previous study had apopulation standard deviation of $677.

5 Construct the confidence interval for the population mean, if c = ) ($2910, $3330)B) ($1987, $2346)C) ($210, $110)D) ($4812, $5342)17)218) In order to set rates, an insurance company is trying to estimate the number of sick days that fulltime workers at an auto repair shop take per year. A previous study indicated that the standarddeviation was days. How large a sample must be selected if the company wants to be 95%confident that the true mean differs from the sample mean by no more than 1 day?A) 31B) 1024C) 141D) 51218)19) Find the critical value, tc, for c = and n = ) ) ) ) )20) Find the value of E, the margin of error, for c = , n =15 and s = ) ) ) ) )21) In a random sample of 28 families, the average weekly food expense was $ with a standarddeviation of $ Determine whether a normal distribution or a t-distribution should be used orwhether neither of these can be used to construct a confidence interval.

6 Assume the distribution ofweekly food expenses is normally ) Cannot use normal distribution or ) Use normal ) Use the )22) A survey of 100 fatal accidents showed that 44were alcohol related. Find a point estimate for p, thepopulation proportion of accidents that were alcohol ) ) ) ) )23) A survey of 280 homeless persons showed that 63 were veterans. Construct a 90% confidenceinterval for the proportion of homeless persons who are ) ( , )B) ( , )C) ( , )D) ( , )23)3 Answer KeyTestname: PRACTICEFINALC4_61) B2) A3) D4) D5) C6) B7) B8) A9) D10) D11) A12) B13) C14) C15) D16) A17) A18) A19) A20) B21) C22) B23) C4