<PRE><B>Question 169683</B>
A chemist is studying the properties of a bronze alloy (mixture) of copper and tin. 
She begins with 10 kg of an alloy that is one fifth tin. 
Keeping the amount of copper constant, she adds small amounts of tin to the alloy. 
Letting x be the total amount of tin added, define 
C(x) = Concentration of tin = Total amount of tin/Total amount of alloy
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C(x) = [(1/5)(10kg)+x]/[10 + x]
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Cheers,
Stan H.
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