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:

n1=50 m1=85 s1=10.2  n2=60 m2=80 s2=8.9  α=0.05 CL=1α=10.05=1920=0.95  x=0

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