Strong chairs A company that manufactures classroom chairs

Chapter , Problem R9.3

(choose chapter or problem)

Strong chairs? A company that manufactures classroom chairs for high school students claims that the mean breaking strength of the chairs that they make is 300 pounds. One of the chairs collapsed beneath a 220-pound student last week. You wonder whether the manufacturer is exaggerating the breaking strength of the chairs. (a) State null and alternative hypotheses in words and symbols. (b) Describe a Type I error and a Type II error in this situation, and give the consequences of each. (c) Would you recommend a significance level of 0.01, 0.05, or 0.10 for this test? Justify your choice. (d) The power of this test to detect M = 294 is 0.71. Explain what this means to someone who knows little statistics. (e) Explain two ways that you could increase the power of the test from (d). s If conditions are met, conduct a significance test about a population proportion.