Question

You wish to test the following claim ( H 1 ) at a significance level of α = 0.005 . H o : μ = 63.1 H 1 : μ < 6 3.1 You believe the population is normally distributed, but you do not know the standard deviation. You obtain a sample of size n = 26 with a mean of ¯ x = 60.6 and a standard deviation of s = 8.5 . What is the critical value for this test? (Report answer accurate to three decimal places.) critical value =

Answer 1

Solution :

This is the left tailed test .

n = 26

df = 26 - 1 = 25

t _0.005,25 = -2.787

Critical value = -2.787