Results 1 to 5 of 5

Math Help - Multile choice question #2

  1. #1
    Newbie
    Joined
    Feb 2011
    Posts
    11

    Multile choice question #2

    Q29: There are four prime no written in ascending order. The product of the
    first three is 385 and that of the last three is 1001.The last no is?
    A. 11
    B. 13
    C. 17
    D. 19
    how?
    Last edited by mr fantastic; February 11th 2011 at 01:39 AM. Reason: Re-titled.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    11,560
    Thanks
    1425
    This one you would just use trial and error.

    Write down the prime numbers up to \displaystyle 19 and work out the products of the four consecutive primes ending in \displaystyle 11,13,17,19.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor

    Joined
    Apr 2005
    Posts
    15,707
    Thanks
    1470
    Why do you assume consecutive primes?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    11,560
    Thanks
    1425
    Quote Originally Posted by HallsofIvy View Post
    Why do you assume consecutive primes?
    Because I stupidly read "ascending order" as "consecutive"...
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Senior Member
    Joined
    Nov 2010
    From
    Staten Island, NY
    Posts
    451
    Thanks
    2
    I think that in this question you can just write down the prime factorizations of the 2 given numbers, and the answer will magically appear.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Multiple choice question.
    Posted in the Statistics Forum
    Replies: 1
    Last Post: October 15th 2011, 05:38 PM
  2. a question about the Axiom of choice
    Posted in the Discrete Math Forum
    Replies: 2
    Last Post: August 9th 2011, 08:36 AM
  3. Multiple choice question #1
    Posted in the Algebra Forum
    Replies: 1
    Last Post: February 11th 2011, 07:52 PM
  4. Multiple Choice Question
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: October 12th 2010, 09:50 AM
  5. Multiple Choice Question
    Posted in the Algebra Forum
    Replies: 4
    Last Post: January 1st 2010, 04:27 AM

Search Tags


/mathhelpforum @mathhelpforum