Question

a researcher found that a cigarette smoker smokes on average 31 cigarettes a day. she feels that this average is too high. she selected a random sample of 8 smokers and found that the mean number of cigarettes they smoked per day was 28. the sample standard deviation was 2.9. at

Answer 1

At 0.01 significance level the hypothesis is rejected.

Null Hypothesis (H₀): The sample data occurs purely from chance.

Alternative Hypothesis (H₁): The sample data is influenced by some non-random cause.

If the p-value of the hypothesis test is less than some significance level (e.g. α = .01), then we can reject the null hypothesis and conclude that we have sufficient evidence to say that the alternative hypothesis is true.

Given that,

x = 28

s = 2.9

μ = 31

n = 8

α = 0.01

Then, the Null Hypothesis : H₀ = 31

          The Alternate Hypothesis : H₁ < 31

The average number of cigeratte smoker  per day is less than 31.

Test Statistics:

t = x -μ / s√n

   = 28 - 31/ 2.9√8

   = -3/ 8.41

   = -0.356

Since the p-value of 0.0046 is less than the significance level of 0.01, the auditor rejects the null hypothesis.

Learn more about Null hypothesis:

brainly.com/question/28920252

#SPJ4