|  | 
| 
 
 
| Question 93069:  hi i have faced problems in GRE like this(this is only example to explian to you)
 there were seperate questions for pirme,even and odd
 the questions were like which of the following is not (prime,even,odd)
 2*(x-2)
 (x-4)+y
 (x+4)*3
 like these please can you tell me from where i can get these types of questions for study please help tell me any website
 thanks
 waiting for response
 zamansoomro@yahoo.com
 Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! which of the following is not (prime,even,odd) 2*(x-2)
 (x-4)+y
 (x+4)*3
 like these please can you tell me from where i can get these types of questions for study please
 ---------------
 You might use Google with search word "prime even odd numbers" .
 But the key to answering this type problem is to consider the result
 if the variable is even or odd.
 For example:
 Consider (x+4)*3
 x is either even or odd
 If x is even, x+4 is even
 When you multiply by three the result is still even
 --------
 If x is odd, x+4 is still odd
 When you multiply an odd by an odd you get an odd result
 ------------
 Therefore (x+4)*3 could be even or it could be odd.
 --------------
 Now, is it prime?
 If it could be even and not equal to 2 it is definitely not prime.
 -----------------
 Conclusion: You cannot say it is always even; you cannot say it is
 always odd; you cannot say it is always prime.
 ---------------------
 Hope that helps and good luck on your GRE.
 Cheers,
 Stan H.
 | 
  
 | 
 |  |  |