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Sum of Consecutive Prime Numbers


Date: 6/29/96 at 16:21:59
From: Anonymous
Subject: Sum of Two Consecutive Prime Numbers

Dear Dr. Math,

Why is it that the sum of two consecutive prime numbers is always 
going to be double a composite number?

Thanks!

Date: 7/10/96 at 10:40:4
From: Doctor Ethan
Subject: Re: Sum of Two Consecutive Prime Numbers

Note that p and q are consecutive primes, so every x between p and q 
is composite.  Since p+q is even, (p+q)/2 is an integer and is 
strictly between p and q; thus it must be composite.

-Doctor Ethan,  The Math Forum
 Check out our web site!  http://mathforum.org/dr.math/

Associated Topics:
Middle School Number Sense/About Numbers
Middle School Prime Numbers

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