# Question

According to one source, 50% of plane crashes are due at least in part to pilot error (http://www.planecrash-info.com). Suppose that in a random sample of 100 separate air-plane accidents, 62 of them were due to pilot error (at least in part.)

a. Test the null hypothesis that the proportion of airplane accidents due to pilot error is not 0.50. Use a significance level of 0.05.

b. Choose the correct interpretation:

i. The percentage of plane crashes due to pilot error is not significantly different from 50%.

ii. The percentage of plane crashes due to pilot error is significantly different from 50%.

a. Test the null hypothesis that the proportion of airplane accidents due to pilot error is not 0.50. Use a significance level of 0.05.

b. Choose the correct interpretation:

i. The percentage of plane crashes due to pilot error is not significantly different from 50%.

ii. The percentage of plane crashes due to pilot error is significantly different from 50%.

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