Performance comparing

A standardized test was administered to thousands of students with a mean score of 85 and a standard deviation of 8. A random sample of 50 students were given the same test and showed an average score of 83.20. Is there evidence to show that this group has a lower performance than the ones in general at 0.05 level?

Result

x=




Step-by-step explanation:

m=85 s=8  n2=50 m2=83.20  α=0.05  Z=N(0,1) z=m2ms/n2=83.2858/501.591  p=P(Z<z)  p=0.0559  α<p x=0



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