A professor

A professor in a typing class found out that the average performance of an expert typist is 85 words per minute. A random sample of 16 students took the typing test and an average speed of 62 words per minute was obtained with a standard deviation of 8. Can we say that the sample students performance is below the standard deviation at the 0.05 level of significance.

Result

x=




Step-by-step explanation:

m=85 s=8  n2=16 m2=83.20  α=0.05  Z=N(0,1) z=m2ms/n2=83.2858/16=910=0.9  p=P(Z<z)  p=0.0559  α<p x=0



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