Question 93017
If the average (arithmetic mean) of x and y is k, which of the following is the average of x, y, and z? 
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If "k" is the average of x and y then (x+y)/2 = k and x+y=2k
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Average of x,y,and z is (x+y+z)/3 = (2k+z)/3 
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Cheers,
Stan H.