Question

In: Statistics and Probability

Consider two populations. A random sample of 28 observations from the first population revealed a sample...

Consider two populations. A random sample of 28 observations from the first population revealed a sample mean of 40 and a sample standard deviation of 12. A random sample of 32 observations from the second population revealed a sample mean of 35 and a sample standard deviation of 14.

(a) Using a .05 level of significance, test the hypotheses H0 : μ1 − μ2 = 0 and H1 : μ1 − μ2 ≠ 0, respectively. Explain your conclusions.

(b) What is the p-value of your result in part (a)? Interpret the p-value.

(c) Construct a 95% confidence interval for the difference between μ1 and μ2. Interpret the confidence interval.

(d) Explain the relationship between your answers in parts (a) and (c).

Solutions

Expert Solution

a)

c)


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