The resting heart rates for 80 women aged 46 55 in a simple random sample are normally distributed with a mean 71 beats per minute and a standard deviation of 6 beats per minute Assuming a 90 confidence level 90 confidence level z score of 1 645 what is the margin of error for the population mean Remember the margin of error ME can be determined using the formula ME 0 66 O 1 10 O 1 31 O 1 73 Z S