A random sample is selected from a population with mean 10

A random sample is selected from a population with mean ? = 100 and standard deviation ? = 10. Determine the mean and standard deviation of the x? sampling distribution with a

Solution

23) Sample mean = pop mean = 100

s = std dev of sample = 10/rt 36 = 1.667

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24) n=100 hence rt n = 10

Mean = 100 and s = 10/10 = 1

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Two populations have mean mu1 =30, mu2 = 25

s1 =2 and s2 =3

mu1-mu2 = 5

Std dev (mu1-mu2) = sd mu1/rtn-1+ sd mu2/rtn-1

= 0.320+0.428

Nearly 1.