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Homework Help: How to solve this equation?

  1. Sep 8, 2004 #1
    The equation is:

    [3.12 (nautical miles)^2] (1.852x10^3 m/1 nautical mile)^2 = 1.07x10^7 m^2

    I don't understand how that answer was reached. The nautical miles cancel out so I assumed I would just multiply 3.12 X 1.852x10^3 to get the same anwer as provided and my answer is nothing close to that. What do I have to do to get the above answer?
  2. jcsd
  3. Sep 8, 2004 #2


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    Homework Helper

    Just multiply it out. Pay attention to what is squared and what is not! :-)
  4. Sep 8, 2004 #3
    That doesn't really help me, I still don't understand.

    I've tried multiplying it out many different ways to no avail.

    For example I tried multiplying it out like so: 3.12^2 X (1.852x10^3)^2 and got this answer: 1.80281088E10

    Obviously that isn't correct. I don't understand why this has to be so hard.
  5. Sep 8, 2004 #4
    first of all its not 3.12^2.... try again and look carefully at the question...
  6. Sep 8, 2004 #5
    Let me clarify, that this problem is an example from my book. It's not an homework assignment or else I never would have had the right answer in the first place. Obviously. I am trying to learn what steps to take to solve for that equation as the book has done. Since it does not do it step by step. I don't see the harm in showing me step by step how to solve for that equation. As the answer is already given. I'm not asking for the answer, just the steps to reach that answer. I learn best by seeing something, an example.

    Like I said this is not a homework problem. I am just doing some work on my own to figure this out as I do not understand how that answer was achieved.
  7. Sep 8, 2004 #6
    lol alright alright...

    [3.12 (nautical miles)^2] (1.852x10^3 m/1 nautical mile)^2 = 1.07x10^7 m^2

    nm = nautical miles

    (3.12nm^2*(1.852*10^3m)^2 3.12nm^2 * (1.852*10^3)^2 m^2
    _______________________ = _______________________________
    1nm^2 1nm^2

    notice that the nm^2 happen to be on the top and bottom. they can cancel out and the answer is left with m^2 for whatever the numbers multiply to.

    ps it might look screwed up. but you'll have to quote me to see it better....
  8. Sep 8, 2004 #7
    Oh, ok I see. I actually had it half way figured out which is why I came back to let you know.

    Thank you for showing me, I really appreciate it.
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