A researcher is working with a normally distributed population with a mean of 27 and standard...

A researcher is working with a normally distributed population with a mean of 27 and standard deviation of 10. If you randomly choose a sample 169 participants, what proportion of the sample means will be less than 25? Show all of your calculations for full credit.

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Expert Solution

Solution :

Given that,

mean = = 27

standard deviation = = 10

n = 169

= 27

= / n = 10/ 169=0.769

P( <25 ) = P[( - ) / < (25-27) / 0.769]

= P(z <-2.60 )

Using z table

= 0.0047

probability= 0.0047

orchestra answered 2 years ago

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