Question

An IQ test is designed so that the mean is 100 and the standard deviation is 18 for the population of normal adults. Find the sample size necessary to estimate the mean IQ score of statistics students such that it can be said with 95% confidence at the sample mean s within 5 Q poln softhe true mea Assume that σ 18 and determine the required sample size using technology. Then determine if this is a reasonable sample size for a real world calculation. The required sample size is.(Round up to the nearest integer.) Would it be reasonable to sample this number of students? O 0 O O Yes. This number of IQ test scores is a fairly large number. No. This number of IQ test scores is a fairly large number. Yes. This number of IQ test scores is a fairly small number. No. This number of IQ test scores is a fairly small number.

Answer 1

Given that sigma = 18 margin at error = E = 5 A 95% confidence level level of significance = alpha = 1 - 0.95 = 0.05 critical value z_alpha/2 = z 0.05/2 z_alpha/2 = 1.96 using one tailed standard normal table \r\n The required sample size is n = [2H_2 sigma/E]^2 = [(1.96)(18)/5]^2 = 49.787 n = 50 The required sample size is 50 would it be reasonable to sample this number of students yes, This number of IQ test scores is a fairly small number.