Statistics for Business: Decision Making and Analysis, 3rd Edition

You Do It

1. 39.

   1. Yes, the p-value is P(X ≥ 5) ≈ 0.007, which rejects H₀ for α = 0.05.

   2. Inspection must produce independent outcomes with constant chance p for finding a defect.

   3. z ≈ 3.5 > 1.645 standard errors above H₀. Reject H₀ for α = 0.05.

   4. The expected number of events is too small. Use binomial methods.

2. 41.

   1. H₀: p ≤ 0.6 versus H_a: p > 0.6; p is the proportion of markets selling out.

   2. A Type I error implies adding an unnecessary delivery (incorrectly reject H₀). A Type II error occurs if we fail to reject H₀ when it's false, missing an opportunity.

   3. Approximately P(Z > 2,438) = 0.0074. Yes.

3. 43.

   1. H₀: p ≥ 0.33 versus H_a: p < 0.33; p is the proportion of all visitors who will indicate a willingness to return.

   2. (b) A Type I error implies intervening ...