According to Thomson Financial, last year the majority of companies reporting profits had beaten estimates. A sample of 162 companies showed that 98 beat estimates, 29 matched estimates, and 35 fell short.
a. What is the point estimate of the proportion that fell short of estimates?
b. Determine the margin of error and provide a 95% confidence interval for the
proportion that beat estimates.
c. How large a sample is needed if the desired margin of error is .05?