<PRE><B>Question 1081224</B>
z-tests
for the first 
z=(52-50)/5/sqrt(9)=2*3/5=1.2
p-value is 0.23 with a two way test and 0.115 with a one way test, which is what I think is desired here.
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n=25, sqrt (25) and 2*5/5=2
p=0.0228 
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n=100 and 2*10/2, and p-value is 0.00003
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As the sample size increases, the z value increases proportional to the sqrt (n).  This means as the size of a sample increases, it is increasingly more difficult for the mean to be further from the postulated true mean.
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