<PRE><B>Question 415950</B>
 The first 100 cost $10 each and the next 200 cost $5 each. How much should Roger pay for the next 100 if the overall average price is to be $10. 
The answer is supposed to be $20 
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Average value Equation: 
(100*10 + 200*5 + 100*x)/400 = 10
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(2000 + 100x) = 4000
100x = 2000
x = $20
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Cheers,
Stan H.</PRE>