Results 1 to 9 of 9

Math Help - $7.11 word problem

  1. #1
    Junior Member
    Joined
    Jul 2007
    Posts
    69
    Awards
    1

    $7.11 word problem

    I need to verify that my answer(logic) is correct. I got this word problem from a magazine recently:
    A person goes into a store and buys 4 items totaling $7.11.
    The price of the 4 items will equal $7.11 if added(of course) but also if multiplied.
    What is the price of each item?

    Kid Funky Fried
    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
    This is an old classic.

    So, what are your answers?. There are only 4 that work perfectly.

    You should be able to check on a calculator.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Jul 2007
    Posts
    69
    Awards
    1

    there are 4?

    Well here is what i did-
    It seemed that I was unable to use alegbra because i could not eliminate enough varibles to solve for any given one. So, because the numbers were to be multiplied, I found all the factors of 711-1,3,9,79,237,and 711.Of these factors I found 3 & 2.37 would be the two numbers that I felt meant the conditions. Having then found all the factors of those numbers I concluded, now it seems in error, that there are no possible solutions.

    Kid
    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
    Try these:

    $1.20, $1.25, $1.50, $3.16
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Junior Member
    Joined
    Jul 2007
    Posts
    69
    Awards
    1

    Great!

    Thanks, can you show me how you got the answers?
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Eater of Worlds
    galactus's Avatar
    Joined
    Jul 2006
    From
    Chaneysville, PA
    Posts
    3,001
    Thanks
    1
    Trial and error. Years ago. This is an old problem.

    Actually, if I remember correctly, I started with 1.2 ,1.25, 1.5.

    These three were just a lucky start and I knew they also have the same sum and product.

    Then it was a matter of finding one more number which made 7.11
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Junior Member
    Joined
    Jul 2007
    Posts
    69
    Awards
    1

    Ok, I found my error.

    Had I factored 7110 and not 711 I would have found the numbers I was looking for.

    Thanks for your help!
    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
    7110=2\cdot{3^{2}}\cdot{5}\cdot{79}
    Follow Math Help Forum on Facebook and Google+

  9. #9
    Junior Member
    Joined
    Jul 2007
    Posts
    69
    Awards
    1

    yes

    those are prime factors correct?
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. word problem - the snow plough problem?
    Posted in the Differential Equations Forum
    Replies: 1
    Last Post: October 13th 2011, 02:02 PM
  2. Replies: 3
    Last Post: January 2nd 2011, 09:20 PM
  3. 1 Word problem and 1 function problem
    Posted in the Algebra Forum
    Replies: 8
    Last Post: April 21st 2010, 09:01 AM
  4. Replies: 2
    Last Post: January 10th 2009, 06:49 AM

Search Tags


/mathhelpforum @mathhelpforum