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Help! Maths!

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Why bother with a post grad course - waste of time? 17-10-2016
    • Thread Starter

    The question reads as follows "Two spheres have radii in rati 5:3. Circle the ratio of their volumes: 5:3, 15:9, 25:9, 125:27". Answer is not what I'm interested in, but more so on how to solve other maths questions like these in the future (Or tomorrow, because I have a test)

    If two spheres have the same radii, then they will be the same volume. Or in this case you have a ratio. If a one spheres is in the ratio 5:3 compared to another sphere, the volume will be in that ratio as well.

    This is because there is only one variable you need when working out volume of a sphere (radius)

     V \propto r^3 , so you have to cube the ratio too, so it will be 53 :33 so 125 : 27 .
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