In a sample of 38 iPhones, 25 had over 98 apps downloaded. Construct a 90% confidence interval for the population proportion of all iPhones that obtain over 98 apps. Assume z0.05 = 1.645
Added by Michelle M.
Step 1
\[ \hat{p} = \frac{\text{number of iPhones with over 98 apps}}{\text{total number of iPhones}} = \frac{25}{38} \approx 0.6579 \] Show more…
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