Question

What are you drinking? Environmental Protection Agency standards require that the amount of lead in drinking water be less than 15 micrograms per liter. Ten samples of water from a particular source have the following concentrations, in units of micrograms per liter. Assume the population standard deviation is o = 4. If appropriate, perform a hypothesis test to determine whether you can conclude that the mean concentration of lead meets the EPA standards. Use the a-0.01 level of significance and the P-value method with the TI-84 calculator. LE 11.7 14.3 11.6 9.6 14.7 15.8 17.5 12.6 8.6 11.5 & Send data al Part: 0/6 Part 1 of 6 Explain why it is necessary to check that the population is approximately normal before performing a hypothesis test. It is necessary to check that the population is approximately normal because (Choose one) X

Answer 1

it is necessary to Check that the population is approximately normal because the sample size is smaller than 30