Results 1 to 11 of 11

Math Help - Need some help please

  1. #1
    Member
    Joined
    Jun 2006
    Posts
    165

    Question Need some help please

    The minimum value of z=4x+10y subject to
    3x+y<=to24
    6x+4y<=to66
    x>=to0,y>=to 0. is.

    My answer after looking at a list of possible answers is 32, is this right.
    a.165
    b.110
    c.44
    d.32
    Thanks for any help given.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Eater of Worlds
    galactus's Avatar
    Joined
    Jul 2006
    From
    Chaneysville, PA
    Posts
    3,001
    Thanks
    1
    Yep, that's what I got.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member

    Joined
    May 2006
    From
    Lexington, MA (USA)
    Posts
    11,740
    Thanks
    645
    Hello, kwtolley!

    Am I reading it wrong?
    Are there typos in the problem?


    The minimum value of z \:=\:4x+10y subject to: \begin{Bmatrix}3x+y\,\leq\,24 \\ 6x+4y\,\leq\,66 \\ x \geq 0\\ y \geq 0\end{Bmatrix} is:

    a)\;165\qquad b)\;110\qquad c)\;44\qquad d)\;32

    Doesn't x = 0,\;y = 0 satisfy the inequalties?

    Follow Math Help Forum on Facebook and Google+

  4. #4
    Eater of Worlds
    galactus's Avatar
    Joined
    Jul 2006
    From
    Chaneysville, PA
    Posts
    3,001
    Thanks
    1
    By Jove, Soroban, I think you're right. Here's the graph.

    Follow Math Help Forum on Facebook and Google+

  5. #5
    Eater of Worlds
    galactus's Avatar
    Joined
    Jul 2006
    From
    Chaneysville, PA
    Posts
    3,001
    Thanks
    1
    Soroban, I just ran this through the Linear Programming solver in Maple and it gave me (0,0) as the minimum. I looked right past the origin.

    Looks like the list of answers is omitting the correct minimum. That's why you're the man and I'm just a dogface .

    Good 'ketch' .
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Member
    Joined
    Jun 2006
    Posts
    165

    Thanks to you both

    Thats what I thought it would be, 32. Thanks so much for checking my answer.
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Global Moderator

    Joined
    Nov 2005
    From
    New York City
    Posts
    10,616
    Thanks
    9
    galactus are you using the program I use? If you are, how you like it?
    Follow Math Help Forum on Facebook and Google+

  8. #8
    Eater of Worlds
    galactus's Avatar
    Joined
    Jul 2006
    From
    Chaneysville, PA
    Posts
    3,001
    Thanks
    1
    I like it a lot. What's even better, it's free. It's that Padowan thing; I downloaded it. I sometimes have trouble getting it to shade what I want to shade, but other than that it's great. Is this what you have?.
    Follow Math Help Forum on Facebook and Google+

  9. #9
    Global Moderator

    Joined
    Nov 2005
    From
    New York City
    Posts
    10,616
    Thanks
    9
    Quote Originally Posted by galactus
    Is this what you have?.
    Same one you have. Great thing it is free. Also safe, cuz many free programs are adware. Finally, do you know it can approximate a set a points with different curves?
    Follow Math Help Forum on Facebook and Google+

  10. #10
    Senior Member
    Joined
    Apr 2006
    Posts
    399
    Awards
    1
    Quote Originally Posted by kwtolley
    The minimum value of z=4x+10y subject to
    3x+y<=to24
    6x+4y<=to66
    x>=to0,y>=to 0. is.

    My answer after looking at a list of possible answers is 32, is this right.
    a.165
    b.110
    c.44
    d.32
    Thanks for any help given.
    As Soroban noted, the minimum value is 0, not on the list. So there is a typo. From this linear programming solver, which you can use to both solve the problem or check your work, the maximum value is 165, answer a.

    If you have linear programming problems to solve in the future, you may want to bookmark that solver.
    Follow Math Help Forum on Facebook and Google+

  11. #11
    Eater of Worlds
    galactus's Avatar
    Joined
    Jul 2006
    From
    Chaneysville, PA
    Posts
    3,001
    Thanks
    1
    Quote Originally Posted by ThePerfectHacker
    Same one you have. Great thing it is free. Also safe, cuz many free programs are adware. Finally, do you know it can approximate a set a points with different curves?
    No, I haven't delved into that feature. It's very user friendly.
    Follow Math Help Forum on Facebook and Google+


/mathhelpforum @mathhelpforum