95% = mean ± 1.96 SEm
1.96 SEm = 200
SEm = SD/√n
A researcher is interested in estimating the average salary of police officers in a large city. She wants to be 95% confident that her estimate is correct. If the standard deviation is $1050,how
large a sample is needed to get the desired information and to be accurate within $200.
1 answer
1 answer