The U.S. Census Bureau conducts a study to determine the time needed to complete the short form. The Bureau surveys 200 people. The sample mean is 8.2 minutes. There is a known standard deviation of 2.2 minutes. The population distribution is assumed to be normal.
If the Census wants to increase its level of confidence and keep the error bound the same by taking another survey, what changes should it make? Think in terms of sample size