Question 1201486
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Answer: 
mean = <font color=red size=4>88</font>
standard deviation = <font color=red size=4>2</font>



Explanation:


xbar = sample mean
The xbar distribution is the distribution of various sample means from the same population.
If we were to repeatedly take random samples of n = 81, compute the sample mean, then this is one of the many xbar values.


The center of the xbar distribution is mu = 88 which is where all of the xbar values should cluster around.


The standard deviation of the xbar distribution is
sigma/sqrt(n)=18/sqrt(81)
=18/9
=2
where sigma is the population standard deviation.
This tells us how spread out the distribution is.
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