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Homework Help: Too simple?

  1. Feb 17, 2008 #1
    http://img180.imageshack.us/img180/9589/simplell9.jpg [Broken]

    Is 1. c) as simple as i think it is?

    I have gone through my notes and can't find anything to do with it, the module for it is Numbers, symmetries and groups, any ideas or do i simple just wack in 13/7 on my calculator and write down the answer?

    Also, 1. d) I don't have a method of working that out.

    I tried this though:

    24/10 + (1)SIGMA(n) 39/(10^2n+1) = 2.43939393939...

    But I don't know how to get this into a fraction from here.
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Feb 17, 2008 #2
    For (d) the trick is to use the fact that 393939... repeats itself. Let [itex]a=2.4\overline{39}[/itex] and compute [itex]10a,\,1000a[/itex] and subtract them.
  4. Feb 17, 2008 #3
    a = 161/66 ;) thanks!

    So i just assume 1.c) is a question made for a 10 year old?
  5. Feb 17, 2008 #4
    Or for a nine and a half! :rofl:
  6. Feb 17, 2008 #5
    Actually, Firepanda, I think I could have solved all of these problems when I was ten ... or maybe a year or two later, I don't recall exactly. In what class did you run into these? I hope it wasn't "Calculus and Beyond"!
  7. Feb 17, 2008 #6
    Well I'm 3 weeks into my Numbers, Symmetries and Groups module for 1st year university maths :P These are also assesed questions, so I can't complain :)
  8. Feb 17, 2008 #7
    Ah ... so maybe they're just making sure that you've got your basics tucked under your belt?
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