Question

Suppose data collected by observers at randomly selected intersections across the country revealed that in a sample of 40 drivers, 20 were using their cell phone.

a. Give a point estimate of p, the true driver cell phone use rate (that is, the true proportion of drivers who are using their cell phone while driving).

b. Compute a 90% confidence interval for p. c. Give a practical interpretation of the interval, part b.

Answer #1

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