Suppose a hospital would like to estimate the proportion of patients who feel that physicians who care for them always communicated effectively when discussing their medical care. A pilot sample of 40 patients found that 28 reported that their physician communicated effectively. Determine the additional number of patients that need to be sampled to construct a 90% confidence interval with a margin of error equal to 2% to estimate this proportion. Part 1
The additional number of patients that need to be sampled is
(Round up to the nearest integer.)