Author:
Christine Farr

A machine is set to fill the small-size packages of M&M candies with 56 candies per bag. A samplerevealed three bags of 56, two bags of 57, one bag of 55, and two bags of 58. To test the hypothesis thatthe mean candies per bag is 56, how many degrees of freedom are there?87196. large department store examined a sample of the 18 credit card sales and recorded the amountscharged for each of three types of credit cards: MasterCard, Visa, and Discover. Six MasterCard sales,seven Visa, and five Discover sales were recorded. The store used an ANOVA to test if the mean sales foreach credit card were equal. What are the degrees of freedom for the F statistic?3 in the numerator, 18 in the denominator6 in the numerator, 15 in the denominator2 in the numerator, 15 in the denominator18 in the numerator, 3 in the denominator7.A random sample of 20 items is selected from a population. When computing a confidence interval forthe population mean, what number of degrees of freedom should be used to determine the appropriate tvalue?192520219 n experimental study is one that _____.attempts to reveal why or how one variable produces changes in anotherattempts to capture a population's characteristics by making inferences from a sample'scharacteristics and testing resulting hypothesesdiscovers answers to the questions who, what, when, where, or how muchinvolves manipulation of one or more variables to determine the effect on another variableA random sample of size 15 is selected from a normal population. The population standard deviation isunknown. Assume the null hypothesis indicates a two-tailed test and the researcher decided to use the0.10 significance level. For what values of t will the null hypothesis not be rejected?To the left of -1.282 or to the right of 1.282To the left of -1.645 or to the right of 1.645To the left of -1.345 or to the right of 1.345Between -1.761 and 1.76112Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones Brothers hasmaintained careful records regarding the time to prepare a return. The mean time to prepare a return is 90minutes and the standard deviation of this distribution is 14 minutes. Suppose 100 returns from this yearare selected and analyzed regarding the preparation time. What assumption do you need to make aboutthe shape of the population distribution of all possible tax preparation times to make inferences about themean time to complete a tax form?

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