Question

A professor administers a standardized test that has a µ = 50 and σ = 6....

A professor administers a standardized test that has a µ = 50 and σ = 6. Her class of 31 students (n = 31) has an average score of 55.

Calculate the z observed for the z test comparing the class mean to the population mean.

Math   Statistics-And-Probability   
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Answer #1

Solution :

Given that,

mean = = 50

standard deviation = = 6

n = 31

= 55

Test statistic = z =

= ( - ) / / n

= (55 - 50) / 6 / 31

Test statistic = z = 4.64

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