Is there a difference in the satisfaction rating of traditional cellphone providers who bill for service at the end of a month often under a contract and prepaid cellphone service providers who bill in advance without a contract? The accompanying table contains the satisfaction rating for 10 traditional cellphone providers and 13 prepaid cellphone service providers.What other assumption is necessary in (a)? A. Since the sample sizes are both less than 30, it must be assumed that the samples are specifically chosen and not independently sampled. B. Since the sample sizes are both less than 30, it must be assumed that the sample sizes are equal. C. Since the sample sizes are both less than 30, it must be assumed that the sample variances are equal. D. Since the sample sizes are both less than 30, it must be assumed that both sampled populations are approximately normal. Assuming that the population variances from both types of cellphone providers are equal, construct, and interpret a 90% confidence interval estimate of the difference between the population means of the two types of cellphone providers. The 90% confidence interval is ___ ≤μ1−μ2≤ ___. Which of the following is the best interpretation of the confidence interval? A. One can say with 90% confidence that the difference between the population mean ratings of the two types of cellphone providers is larger than the upper bound. B. One can say with 90% confidence that the difference between the population mean ratings of the two types of cellphone providers is smaller than the lower bound. C. One can say with 90% confidence that the difference between the population mean ratings of the two types of cellphone providers falls outside this interval. D. One can say with 90% confidence that the difference between the population mean ratings of the two types of cellphone providers falls in this interval. What conclusions can you reach about the satisfaction rating of traditional cellphone providers who bill for service at the end of a month often under a contract and prepaid cellphone service providers who bill in advance without a contract? Since the hypothesis test __A__ the null hypothesis and the confidence interval __B__ 0, conclude that there is __C__ in mean satisfaction ratings between the two types of providers. A: does not reject or rejectB: contains or does not containC: no difference or a difference Cellphone Provider RatingsType of ProviderRating87TraditionalTraditional88Traditional81TraditionalTraditional7675Traditional72TraditionalTraditionalTraditionalTraditional747269Prepaid-878785PrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaid益79817875747472697268PrintDoneo difference in the mean ratings between the two types of cellphone providers.

Question

Is there a difference in the satisfaction rating of traditional cellphone providers who bill for service at the end of a month often under a contract and prepaid cellphone service providers who bill in advance without a​ contract? The accompanying table contains the satisfaction rating for 10 traditional cellphone providers and 13 prepaid cellphone service providers.What other assumption is necessary in​ (a)? A. Since the sample sizes are both less than​ 30, it must be assumed that the samples are specifically chosen and not independently sampled. B. Since the sample sizes are both less than​ 30, it must be assumed that the sample sizes are equal. C. Since the sample sizes are both less than​ 30, it must be assumed that the sample variances are equal. D. Since the sample sizes are both less than​ 30, it must be assumed that both sampled populations are approximately normal. Assuming that the population variances from both types of cellphone providers are​ equal, construct, and interpret a 90​% confidence interval estimate of the difference between the population means of the two types of cellphone providers. The 90​% confidence interval is ___ ≤μ1−μ2≤ ___. Which of the following is the best interpretation of the confidence​ interval? A. One can say with 90​% confidence that the difference between the population mean ratings of the two types of cellphone providers is larger than the upper bound. B. One can say with 90​% confidence that the difference between the population mean ratings of the two types of cellphone providers is smaller than the lower bound. C. One can say with 90​% confidence that the difference between the population mean ratings of the two types of cellphone providers falls outside this interval. D. One can say with 90​% confidence that the difference between the population mean ratings of the two types of cellphone providers falls in this interval. What conclusions can you reach about the satisfaction rating of traditional cellphone providers who bill for service at the end of a month often under a contract and prepaid cellphone service providers who bill in advance without a​ contract? Since the hypothesis test __A__ the null hypothesis and the confidence interval __B__ 0, conclude that there is __C__ in mean satisfaction ratings between the two types of providers.  A: does not reject or rejectB: contains or does not containC: no difference or a difference Cellphone Provider RatingsType of ProviderRating87TraditionalTraditional88Traditional81TraditionalTraditional7675Traditional72TraditionalTraditionalTraditionalTraditional747269Prepaid-878785PrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaidPrepaid益79817875747472697268PrintDoneo difference in the mean ratings between the two types of cellphone providers.

Accepted Answer

(a) Here the sample sizes are less than 30. so, we have to conduct a two-sample T-test 
Assumptions…