Question

A group of 51 randomly selected students have a mean score of
29.5 with a sample standard deviation of 5.2 on a placement test.
What is the 95% confidence interval for the

mean score, μ, of all students taking the test?

Critical error=

Margin of error=

confidence interval=

Answer #1

# critical error= 5.2/√51 = 0.7281

# margin of error= 2.009* 0.7281= 1.4628

# c.i= ( 28.037,30.963)

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