1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Please i need help with Base Mathematics

  1. May 16, 2007 #1
    When fractions F1 and F2 are written as base n decimals, F1=(.7373)base n and F2=(.3737)base n. In base m, F1=(.5252)base m and F2=(.2525) base m. Find (m+n). No trial and error please.
  2. jcsd
  3. May 16, 2007 #2


    User Avatar
    Staff Emeritus
    Science Advisor

    Saying "F1= (.7373) base n" means F1= 7/n+ 3/n2+ 7/n3+ 3/n4. Similarly, saying "F1= (.5252) base m" means that F1= 5/m+ 2/m2+ 5/m3+ 2/m4. Putting those together you know that 7/n+ 3/n2+ 7/n3+ 3/n4= 5/m+ 2/m2+ 5/m3+ 2/m4. Likewise, F2= (.3737) base n and F2= (.2525) base m gives 3/n+ 7/n2+ 3/n3+ 7/n4= 2/m+ 5/m2+ 2/m3+ 5/m4. That gives you two equations to solve for the two unknown numbers m and n.

    Edited to replace "y/n3" by "7/n3". My finger slipped!
    Last edited: May 18, 2007
  4. May 16, 2007 #3
    where are you getting y/n^3 from
    I tried doing this method without the y variable and was not able to solve for it. I came up with some crazy nubers. Can you please explain further?
  5. May 16, 2007 #4
    Im not positive but i think halls of ivy meant 7 and not y, as you can see, they are right nnext to each other on the keyboard
  6. May 17, 2007 #5
  7. May 18, 2007 #6
    It seems to me that you're supposed to spot the weird symmetry in the numbers here. '7373', '3737', '5252', '2525'. HallsofIvy outlines a general method of solving this problem when the given numbers have no special pattern, but f:grumpy:k only knows how you'd solve those simultaneous equations!

    My thoughts. Try adding F1 and F2 in base m and in base n. Assume, just to make it easier, that n>10 and m>7 (if that's not the case I'm sure it'll turn up in some contradiction or other)

    (eta: well, I'm not making much progress... but I still think that it's important to note the symmetry here. It means something, I'm sure of it.)
    Last edited: May 18, 2007
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Please i need help with Base Mathematics
  1. I need help please? (Replies: 2)