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Could you show me a simple way to work these equations out? Watch

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    I know this is probably very easy, but I just can't get my head round it, how would you go about working out the following equations?

    2k/5 - k/2 = 1

    a/3 + a/5 = 1

    x/2 + x/3 + x/4 = 1

    Many thanks
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    (Original post by theoallen)
    I know this is probably very easy, but I just can't get my head round it, how would you go about working out the following equations?

    2k/5 - k/2 = 1

    a/3 + a/5 = 1

    x/2 + x/3 + x/4 = 1

    Many thanks
    k\left(\frac{2}{5} - \frac{1}{2}\right) = 1 \iff -\frac{k}{10} = 1.

    i,e: 2/5 lots of k minus half a lot of k gives -1/10 lots of k.

    So now you want to find a number such that if you multiply it by -1 and divide it by 10 you get 1.

    This number is trivially k = -\frac{10}{1}.

    Can you go through a similar procedure for the other questions now?

    What is a/3 + a/5? i.e: 1/3 lots of a added to 1/5 lots of a?
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    (Original post by Zacken)
    k\left(\frac{2}{5} - \frac{1}{2}\right) = 1 \iff -\frac{k}{10} = 1.

    i,e: 2/5 lots of k minus half a lot of k gives -1/10 lots of k.

    So now you want to find a number such that if you multiply it by -1 and divide it by 10 you get 1.

    This number is trivially k = -\frac{10}{1}.

    Can you go through a similar procedure for the other questions now?

    What is a/3 + a/5? i.e: 1/3 lots of a added to 1/5 lots of a?
    Okay so I did that and got an answer of 9, but e book says the answer is 6, what did I do wrong?
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    (Original post by theoallen)
    Okay so I did that and got an answer of 9, but e book says the answer is 6, what did I do wrong?
    Can't tell what question you're talking about.

    Can't read minds and don't know what you've done. So you'll need to show me what you've done before I can point out where you've gone wrong.
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    (Original post by Zacken)
    Can't tell what question you're talking about.

    Can't read minds and don't know what you've done. So you'll need to show me what you've done before I can point out where you've gone wrong.
    The 2k/3 - k/2 = 1 question. I keep running around in circles. I don't understand how you got k\left(\frac{2}{5} - \frac{1}{2}\right) = 1 \iff -\frac{k}{10} = 1 where did the 1/2 come from? And how did you get the -k/10?

    And then when I put the right answer 6 in, I multiply it by -1 and divide it by 10 but get 0.5?

    I'm literally so so confused
 
 
 
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