Sponsored Ad:
See the top rated post in this thread. Click here

Results 1 to 3 of 3

Thread: Prime number problem

  1. #1
    Trying to make mom and pop proud
    Join Date
    Feb 2012
    Posts
    11
    Rep Power
    9


    Good post? Yes | No

    Prime number problem

    Sponsored Ad:
    P is a prime number. If 6p is between 15 and 95, which of the following can be a value of 7p + 2?

    A. 15
    B. 79
    C. 121
    D. 65
    E. 21
    Last edited by nafishasan; 02-06-2012 at 07:01 AM.

  2. #2
    Trying to make mom and pop proud
    Join Date
    Feb 2012
    Posts
    10
    Rep Power
    9


    Good post? Yes | No
    Prime number is its divisor is either 1 or itself.
    15 < 6p < 95, divided by 6.
    2.5 < p < 15.83
    Since we want 7p + 2, we need to make the middle p to 7p + 2
    multiply the inequality by 7 then plus 2
    33.3 < 7p < 110.81
    35.3 < 7p+2 < 112.81
    ACE is outside of the inequality. 65 is not a prime number.
    The answer is B, 79.

  3. #3
    Within my grasp! sandeep_chads's Avatar
    Join Date
    Jan 2007
    Posts
    437
    Rep Power
    15


    1 out of 1 members found this post helpful. Good post? Yes | No
    Just put the values - It shouldn't take any time since the calculations are fairly easy:

    p = prime
    P = 3, 5, 7, 11, 13,
    6P = 18,30, 42, 66, 78,
    7P+2 = 23, 37, 51, 79, 93
    Hey Harvard, I am right here!!
    rep me if I made some sense

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Prime Number Problem
    By lastnightilie in forum GRE Math
    Replies: 2
    Last Post: 06-29-2011, 11:12 PM
  2. Number Properties : prime number
    By Gmater-1 in forum GMAT Problem Solving
    Replies: 3
    Last Post: 12-27-2007, 09:19 PM
  3. Number Properties: prime number addition
    By Gmater-1 in forum GMAT Problem Solving
    Replies: 3
    Last Post: 12-27-2007, 03:32 PM
  4. DS problem - prime number multiples
    By Sargataur in forum GMAT Data Sufficiency
    Replies: 12
    Last Post: 03-09-2005, 04:32 PM
  5. prime number problem
    By Dave710 in forum GMAT Math
    Replies: 9
    Last Post: 03-07-2005, 06:45 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •