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Math Help - Simple equation solving

  1. #1
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    Simple equation solving

    Hi,

    Im new to this forum, so I hope im i line with posting correctly and everything.
    Ive totally forgot how to solve simple equations

    (100 - S) = 8,042 * S,

    How would one solve this?
    Thanks in advance.
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  2. #2
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    Re: Simple equation solving

    Quote Originally Posted by desperadoMan View Post
    Hi,

    Im new to this forum, so I hope im i line with posting correctly and everything.
    Ive totally forgot how to solve simple equations

    (100 - S) = 8,042 * S,

    How would one solve this?
    Thanks in advance.
    Start by adding S to both sides: 100 = 8043*S ....
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  3. #3
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    Re: Simple equation solving

    Oh, I think I figured it out myself. Unfortunately in my case, math is forgotten over time

    8,042 * S = S - 100 ((adding S)
    9,042S = 100
    S = 100/9,024
    S = 11.06
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  4. #4
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    Re: Simple equation solving

    Back to school, Desperado?

    Seems like you're trying to play hockey without skates

    Lets do one similar to yours:
    10 - 2a = 803a (2a means 2 * a, 803a means 803 * a)
    add 2a to both sides:
    10 - 2a + 2a = 803a + 2a
    10 = 805a ...still with me?
    now wrap up:
    a = 10/805
    a = .01242...

    Now go do yours similarly...
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  5. #5
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    Re: Simple equation solving

    Quote Originally Posted by desperadoMan View Post
    Oh, I think I figured it out myself. Unfortunately in my case, math is forgotten over time

    8,042 * S = S - 100 ((adding S)
    9,042S = 100
    S = 100/9,024
    S = 11.06
    Your equation is different to the one in post #1. Why S - 100? In post #1 you wrote 100 - S.

    Post #2 tells you what to do ....
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  6. #6
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    Re: Simple equation solving

    Quote Originally Posted by desperadoMan View Post
    Oh, I think I figured it out myself. Unfortunately in my case, math is forgotten over time

    8,042 * S = S - 100 ((adding S)
    This is not your original problem. Your original problem was 8,042*S= 100- S. For the original problem, adding S is correct and you get

    9,042S = 100
    You didn't "add S", you added 1000 S!

    S = 100/9,024
    S = 11.06
    Oh, wait, you are using the European notation- 8,042 means "8 and 42 thousandths" which I would write as "8.042". In that case you are correct. I notice that mr fantastic made the same assumption. We wouldn't have been fooled if there hadn't been exactly three decimal places!!

    Added in second edit: But then why did you use '.' in your final answer?

    The correct answer is either 11,08 (NOT 11,06) if you are using the "," to separate whole number from decimal part or 0.011 if you are using "." with "," separating thousands.
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  7. #7
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    Re: Simple equation solving

    Yea back to schoo. And im not going to say what course im studying, after asking for this problem

    I did yours, and mine the same way as how Mr-fantastic said. Donno why, just forgot it
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  8. #8
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    Re: Simple equation solving

    Quote Originally Posted by HallsofIvy View Post

    The correct answer is either 11,08 (NOT 11,06) if you are using the "," to separate whole number from decimal part or 0.011 if you are using "." with "," separating thousands.
    The original problem is : 100 - S = 8,042 * S (EIGHT POINT ZERO FOUR TWO). So in US notation that would be with a "." right? sorry for the confusion.

    I think the answer is infact 11,06, you wrote 9.024 instead of 9.042
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