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Multiplying 3+9

Date: Tue, 15 Nov 94 9:45:39 EST
From: Binford M.S. Gifted Program
Subject: math question



Date: Tue, 15 Nov 1994 11:11:32 -0500 (EST)
From: Dr. Ethan
Subject: Daniel's question


        What a neat use of multiplication and addition.  Before I answer 
I wanted to point out to you that the pattern is broken at one point. 
Did you mean for that to be the case?  Just in case you didn't I will 
answer both ways.  

First your way.

(3+9(3(3+9(3+9(3+9(3+9(3+9))))))) = 2192187

Or you might have meant

(3+9(3+9(3+9(3+9(3+9(3+9(3+9)))))))= 6576582

Why don't you try to do this on a calculator and write down what 
you get after each step and see if you can get a pattern.

        Ethan - Doctor On Call
Associated Topics:
Elementary Multiplication

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