Question 1051302
 At the beginning of an experiment, there are 400 grams of contaminants. Each hour, a fourth of the contaminants are filtered out. 
A.Formulate a recursive sequence modeling the number of grams after n hours.
a(n) = 0.75*a(n-1)
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B.Use the model to calculate the amount of contaminants after the third hour of the experiment. 
Ans: 400 ; (3/4)400 = 300 ; (3/4)300 = 900/4  ; (3/4)900/4 = 2700/16 = 168.75g's
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Cheers,
Stan H.
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