2 Scientists can use highperformance liquid chromatography t

2. Scientists can use high-performance liquid chromatography to determine the amount of drug in a tablet. Twenty-five tablets were produced at each of two different sites. Drug concentrations, measured as a percentage, for the tablets produced at the two different sites are found in column C6 and C7 in the Minitab data file. At the 0.05 significance level, can a researcher conclude from these data that there is a significant difference between the mean concentration in tablets produced at Site 1 and Site 2?

c. At the 0.05 significance level, can the researcher conclude from these data that there is a significant difference between the mean concentration in tablets produced at Site 1 and Site 2?

i.State the null and alternative hypotheses.

ii.State the significance level for this problem.

iii.Calculate the test statistic.

iv.Calculate the P-value and include the probability notation statement.

v.State whether you reject or do not reject the null hypothesis.

vi.State your conclusion in context of the problem (i.e. interpret your results).

d. Construct a 95% confidence interval for the above data. Interpret this confidence interval.

Solution

1) Null Hypothesis H₀ : there is no significant difference between the mean concentration in tablets produced at Site 1 and Site 2

against

Alternative hypothesis H₁ : there is a significant difference between the mean concentration in tablets produced at Site 1 and Site 2 ( two tailed)

2) los = 0.05

3) test statistics = t statistics = (xbar - ybar)/ s* Sqrt (1/25 + 1/ 25) where s = pooled standart deviation folows t distribution with n1 +n2 -2 d.f . Minitab file is not visible

4) if p-value > 0.05 then we will fail to reject the null hypothesis

95% CI is ( (xbar - ybar) - t_n1+n2-2,_0.025 * s*sqrt (1/25 + 1/ 25) , (xbar - ybar) + t_n1+n2-2,_0.025 * s*sqrt (1/25 + 1/ 25))