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    • Thread Starter

    I was meant to do a quick 30 minute revision session on inverse and direct proportion. However, when answering some inverse proportion questions I needed to make the denominator of fraction the subject of a formula.

    The question is to find the value of d when I is 12.5

    Here's the formula with the substituted values:

    12.5 (inversely proportional) 200 (the constant or k) x 1/d squared

    I feel stupid for not being able to do such a simple action...
    • Thread Starter

    SOLVED: managed to do it by myself, coincidentally a few minutes after posting this thread.


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