In a sample of 84 people who have had strokes the average ch

In a sample of 84 people who have had strokes, the average cholesterol level was 254 with a standard deviation of 49.3. In order to test the hypothesis (at the 10% level of significance) that the average cholesterol level of people who have had strokes was at least 240, what is the critical value? (please round your answer to 2 decimal places)

Solution

alpha = 0.1

this is a left tailed test

CRITICAL VALUE Z(0.1) = 1.645 = 1.65