A marketing manager for a cell phone company claims that the percentage of children aged 8- 12 who have cell phones differs from 55%. In a survey of 880 children aged 8-12 by a national consumers group, 450 of them had cell phones. a. Can you conclude that the manager's claim is true? State your hypotheses and conclusion and interpret the results. Use an α = 0.01 level of significance and the Pvalue method using your table of statistical values. b. Construct 98% confidence interval for the proportion of the children aged 8-12 who have cellphone and interpret it.

A marketing manager for a cell phone company claims that the percentage of children aged 8- 12 who have cell phones differs from 55%. In a survey of 880 children aged 8-12 by a national consumers group, 450 of them had cell phones. a. Can you conclude that the manager's claim is true? State your hypotheses and conclusion and interpret the results. Use an α = 0.01 level of significance and the Pvalue method using your table of statistical values. b. Construct 98% confidence interval for the proportion of the children aged 8-12 who have cellphone and interpret it.

College Algebra (MindTap Course List)

12th Edition

ISBN:9781305652231

Author:R. David Gustafson, Jeff Hughes

Publisher:R. David Gustafson, Jeff Hughes

Chapter8: Sequences, Series, And Probability

Section8.7: Probability

Problem 58E: What is meant by the sample space of an experiment?

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