# Using Excel to Run a t-test on the context of a Case Study of Inferential Statistics

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$\begin{array}{cc} & {{H}_{0}}:{{\mu }_{D}}=0 \\ & {{H}_{A}}:{{\mu }_{D}}\ne 0 \\ \end{array}$
• Assumptions: In order to apply the t-test we need to show that the differences are normally distributed. We tested for normality at the 0.05 significance level, and we found that we cannot reject the null hypothesis of normality at the 0.05 significance level.
$t = \frac{\bar{D}-{{\mu }_{D}}}{{{s}_{D}}/\sqrt{n-1}}=\frac{3-0}{10.57/\sqrt{24}} = 1.390439$ ${{t}_{c}}=2.064$
• The sample size is not big enough to approximate by a normal distribution. It would be recommended to increase the sample size.