the population standard deviation, math homework help

the population standard deviation, math homework help

Assume that a simple random sample has been taken, the population standard deviation is not known, and the population is normally distributed. Medical researchers studying cochlear implants, devices placed behind the bone in the ear to improve hearing, found the following number of implants over the last twelve years in children under 3 years old. Use a 90% confidence level and the following sample data:40   90   99   120  150  220  300  320  460  520  600  650Find the margin of error E that corresponds to the above statistics and confidence level. Give your answer with one decimal, e.g., 1223.4 .