Thursday, March 26, 2009

March 26, 2009

The positive integers A, B, A – B, and A + B are all prime numbers. The sum of these four primes is...

(A) even
(B) divisible by 3
(C) divisible by 5
(D) divisible by 7
(E) prime

Interactive version of problem and solution.



Buy The Contest Problem Book VIII