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  • Maths people, I am stuck!

    I have a formula D = (A*B*C)/10000 where all values are %.
    If I know the ratio between A, B & C and I know value D, what formula do I use to individually calculate A, B & C?
    I got twisted in knots yesterday and made my head hurt, even though I know I should be able to do this.
    A:B:C = 2:47:51 if it helps!

  • I know value D

    What is it?

    10000D = A × (47/2)A × (51/2)A

    = A³ × (47 × 51)/(2 × 2)

    so

    A³ = (10000/((47 × 51)/(2 × 2))) × D

    so

    A = ∛(16.6875260743 × D)

    Once you know the value of D, you can evaluate A, then B and C are simple fractions of that.

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