<PRE><B>Question 321276</B>
 The mean price of computers at an electronics store is $850, with a standard deviation of $90. 
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A random sample of 21 televisions is drawn from this population. What is the probability that the mean price of the sample is less than $830? 
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mean of the distribution of sample means = 850
std of the distribution of sample means = 90/sqrt(21)
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t(830) = (830-850)/[0.90/sqrt(21)] = -1.0184
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P(x&lt; 830) = P(t&lt; -1.0184 when df=20) = 0.1603
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Cheers,
Stan H. 
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