December 2014
Problem of the Month

Prime Interest



Here is an interesting cross number puzzle.   Place the nine digits 1 through 9 in the grid below, one digit per box, so that the three-digit numbers formed fit the clues.

  1          
   
    		  2          
   
    		  3          
   
   
  4          
   
    		   
  5          
   
    		   


ACROSS
    1. A number with decreasing digits
    4. A prime number
    5. A prime number

DOWN
    1. A prime number
    2. A prime number
    3. A prime number

DIAGONAL
    1. A prime number
    3. A prime number




Solution to the Problem:

           
  8  
    		           
  6  
    		           
  4  
   
           
  2  
    		           
  5  
    		           
  1  
   
           
  7  
    		           
  3  
    		           
  9  
   




Correctly solved by:

1. James Alarie Flint, Michigan
2. Chad Fore Gate City, Virginia
3. Marley Newton Mountain View High School,
Mountain View, Wyoming


Send any comments or questions to: David Pleacher