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    Need help with a maths question Conor Lee

    Here is a fraction: x over blank (x/ )

    The denominator of the fraction is 5 more than the numerator.

    If 1 is added to the numerator and 2 is subtracted from the denominator, the fraction will become 4/5. Find the fraction.

    need the answer explained

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      x+1/x+5 =4/5 solve this equation

      Explained, if demon is 5 more : x/x+5

      then add one and subtract 2 : x+1/x+5

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      numerator: x

      denominator: 5 more than x: x+5

      current fraction: x/x+5

      add 1 to the numerator: x + 1

      subtract 2 from the denominator: x+5 -2 (which is x+3 because 5-2=3)

      so the fraction is now x+1/x+3

      the question says that this new fraction is equal to 4/5

      so x+1/x+3 = 4/5

      cross multiply across the equal sign: (x+1)(5) = (x+3)(4)

      multiply out: 5x+5 = 4x+12

      bring xs to the left and numbers to the right: 5x-4x = 12-5


      now we know that x=7, so we can sub 7 into the original fraction given in the first two lines of the question: x/x+5

      Sub in 7 anywhere that there is an x: 7/7+5

      =7/12 is the fraction!

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      This is a simultaneous equation-a father and his son have a combined age of 52.8 years ago the father was 8 times the sons age .write and equation in x and y

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