The article ?Report: More Than Half of DC-Area Millennials Are Using Ride-Hailing Apps? (washingtonian.com/2016/06/23/report-half-dc -area-millennials-using-ride hailing-apps/, June 23, 2016, retrieved May 4, 2017) refers to a study summarizedat the following site: wbaresearch.com /wp-content/uploads/2016/06/Transportation -MarkeTrak-Spring-20161.pdf (retrieved May 4, 2017).

The study indicates that 21% of Washington-area adults who are 55 years old and older have used transportation apps such as Uber or Lyft at least once.

Suppose that a small local transportation service for older residents is monitoring usage of app-based transportation. The service conducted a survey of a random sample of 21 of its regular customers who are 55 or older and found that 3 of them had tried Uber or Lyft at least once.

a. Would it be appropriate to use the large-sample confidence interval for a population proportion to estimate the proportion of the transportation service customers who have tried Uber or Lyft at least once? Explain.

b. Would it be appropriate to use a bootstrap confidence interval for a population proportion to estimate the proportion of the transportation service customers who have tried Uber or Lyft at least once? Explain.

c. Use the accompanying output from the Shiny app to report a 95% bootstrap confidence interval for the population proportion of customers 55 or older who have used Uber or Lyft at least once. Interpret the confidence interval in context.

d. Is the value obtained in the study for Washington-area adults who are over 55 years old who have used Uber or Lyft at least once (21%) in the bootstrap confidence interval? What does this indicate?

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Bootstrap Distribution 200 100 0.2 0.3 Sample Proportion 0.5 Observed Sample Proportion Standard Error Conf Level 0.333 6% Lower Bound Upper Bound sof Bootstrap Samples 0.000 0.143 0.078 1000 Auanbay