The null and alternate hypotheses are:
H0 : μ1 = μ2
H1 : μ1 ≠ μ2
A random sample of 9 observations from one population revealed a sample mean of 25 and a sample standard deviation of 4.0. A random sample of 4 observations from another population revealed a sample mean of 29 and a sample standard deviation of 4.6.
At the 0.01 significance level, is there a difference between the population means?
a) State the decision rule. (Negative amounts should be indicated by a minus sign. Round your answers to 3 decimal places.) The decision rule is to reject H0 if t <______ or t>_______
b) Compute the pooled estimate of the population variance. (Round your answer to 3 decimal places.)
c) Compute the test statistic.(Negative amount should be indicated by a minus sign. Round your answer to 3 decimal places.)
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