A random sample of n = 100 scores is selected from a normal population with a...

A random sample of n = 100 scores is selected from a normal population with a mean of μ = 60 and a standard deviation of σ = 20. What is the probability of obtaining a sample mean greater than M = 57?

Solutions

Expert Solution

Solution :

Given that,

mean = = 60

standard deviation = = 20

n=100

= =60

= / n = 20 / 100 = 2

P( >57) = 1 - P( <57 )

= 1 - P[( - ) / < (57-60) /2 ]

= 1 - P(z < -1.5)

Using z table

= 1 - 0.0668

= 0.9332

probability=0.9332

orchestra answered 1 year ago

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