Author:
Christine Farr

Question 1 of 20A manufacturer of flashlight batteries took a sample of 13 batteries from a day’s production and used themcontinuously until they failed to work. The life lengths of the batteries, in hours, until they failedwere: 342, 426, 317, 545, 264, 451, 1049, 631, 512, 266, 492, 562, and 298.At the .05 level of significance, is there evidence to suggest that the mean life length of the batteriesproduced by this manufacturer is more than 400 hours?A.Yes, because the test value 1.257 is less than the critical value 2.179B.No, because the test value 1.257 is greater than the critical value 1.115C.Yes, because the test value 1.257 is less than the critical value 1.782D.No, because the p-value for this test is equal to .1164Reset SelectionQuestion 2 of 201.0 PointsA lab technician is tested for her consistency by taking multiple measurements ofcholesterol levels from the same blood sample. The target accuracy is a variance inmeasurements of 1.2 or less. If the lab technician takes 16 measurements and thevariance of the measurements in the sample is 2.2, does this provide enough evidence toreject the claim that the lab technician’s accuracy is within the target accuracy?Compute the value of the appropriate test statistic.A.t = 27.50B. X^2=30.58C. z= 1.65D X^2= 27.50Question 3 of 20Which of the following statements are true of the null and alternative hypotheses?A.It is possible for both hypotheses to be trueB.Both hypotheses must be trueC.Exactly one hypothesis must be trueD.It is possible for neither hypothesis to be true1.0 Points1.0 PointsQuestion 4 of 20Smaller pvalues indicate more evidence in support of the:A.null hypothesisB.quality of the researcherC.alternative hypothesisD.the reduction of varianceQuestion 5 of 201.0 PointsThe form of the alternative hypothesis can be:A.neither one nor two-tailedB.one-tailedC.one or two-tailedD.two-tailedQuestion 6 of 201.0 PointsIn an article appearing in Today’s Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the :sample mean number of calories per serving to be 78 with a sample standard deviation of 7.A. H0: μ=75, H1: μB. H0: μ ≤ 75, H1: μ > 75c. H0: μ≥ 75, H1: μ < 75d. H0: μ= 75, H1: μ >75Question 7 of 201.0 PointsIf a teacher is trying to prove that a new method of teaching economics is more effective than a traditional one, he/she will conduct a:A.one-tailed testB.two-tailed testC.confidence intervalD.point estimate of the population parameterQuestion 8 of 20A type II error occurs when:A.the test is biasedB.the null hypothesis is incorrectly rejected when it is trueC.the null hypothesis is incorrectly accepted when it is falseD.the sample mean differs from the population meanQuestions 9 of 20Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies?

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