Confidence Interval

The average grade of 50 students senior students in a statistics class is 85 with a standard deviation of 10.2 while a group of 60 senior students got an average of 80 with a standard deviation of 8.9, can the difference in the mean grade be attributed to chance, using a 0.05 level of significance?

Correct answer:

x =  0

Step-by-step explanation:

$$\begin{gathered} n_1=50 \\ {m}_1=85 \\ {s}_1=10.2 \\ {n}_2=60 \\ {m}_2=80 \\ {s}_2=8.9 \\ \alpha =0.05 \\ CL=1-\alpha =1-0.05={\displaystyle \frac{19}{20}}=0.95 \\ x=0 \end{gathered}$$

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