Discussion
If x and y are prime numbers, then which one of the following cannot equal x – y ?
*This question is included in Nova Press: Set B  Substitution, question #10
(A)  1 
(B)  ... 
(C)  ... 
(D)  ... 
(E)  ... 
(F)  ... 
The solution is
Posted: 12/15/2013 06:51
If following the first given method, why can't we assume x=15 and y=2 and thus make C be 13?
Posted: 12/16/2013 16:55
Olga, as the solution says, 15 is not prime.
Posted: 12/22/2014 11:20
Which are the prime numbers?
Posted: 11/12/2016 13:57
1 3 5 7 11 13 17 19 ...
Posted: 11/12/2016 13:57
Prime  prime is always even ?
Posted: 11/12/2016 20:32
Hi Maud,
The only even prime number is 2. All other prime numbers are odd.
Nova Press
The only even prime number is 2. All other prime numbers are odd.
Nova Press
Posted: 05/02/2017 22:33
Your answer is 1. I think the answer should be one. One is a difference between 3 and 2 which are prime numbers.

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