A sociologist plans to conduct a survey to estimate the percentage of adults in the US who believe in astrology. In a random survey of 250 US adults, 65 said they said that they believed in astrology.
(a) Find the sample statistic,
.
(b) By hand, find the standard error, SE, and construct a 90% confidence interval using the z* found in the first question above.
(c) Sketch the normal distribution and identify the position of the sample statistic found in part (a) and label the endpoints of the confidence interval found in part (b).