Question 708312
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Use *[tex \LARGE \overline{x}\ =\ \frac{1}{n}\sum_{i=1}^n\,x_i] where *[tex \LARGE x_i] is the *[tex \LARGE i]th data element of *[tex \LARGE n] data elements


to find the mean.  Just add up all of the numbers in the column under Bedrooms (or Bathrooms for part (b)), and then divide by the number of pieces of data.  I used *[tex \LARGE \overline{x}] because you are dealing with a sample (mnay more than 105 homes were sold in the Phoeniz, AZ area in a year.).  If you are considering this set of data to represent the entire population, use *[tex \LARGE \mu] instead of *[tex \LARGE \overline{x}].


and then you have to decide whether you are calculating the standard deviation for this sample as if it were the entire population or you are using this sample to to estimate the standard deviation of the entire population. 



In the first case calculate the <i>population</i> standard deviation using *[tex \LARGE \sigma\ =\ \sqrt{\frac{1}{n}\,\sum_{i=1}^n\,\left(x_i\ -\ \mu\right)^2] or in the second case calculate the <i>sample</i> standard deviation using:  *[tex \LARGE s\ =\ \sqrt{\frac{1}{n\,-\,1}\,\sum_{i=1}^n\,\left(x_i\ -\ \overline{x}\right)^2]


You can do your own arithmetic.  Have fun.


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
<font face="Math1" size="+2">Egw to Beta kai to Sigma</font>
My calculator said it, I believe it, that settles it
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