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    does anyone understand this question and could possibly help?
    it is:
    'a sphere and a cylinder have equal volumes.
    the sphere has radius 3r. the cylinder has radius 2r and height h.
    find h in terms of r'.

    i'm so confused could someone possibly attempt to explain it?
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    Formulas we need:
    Volume of sphere of radius r  = \frac{4}{3} \pi r^3
    Volume of cylinder of radius r and height h  = \pi r^2 h



    Volume of sphere of radius 3r  = \frac{4}{3} \pi (3r)^3 = \frac{4}{3} \pi 27r^3 = 36 \pi r^3
    Volume of cylinder of radius 2r and height h  = \pi (2r)^2 h = 4 \pi r^2 h

    We are given that these volumes are equal so 36 \pi r^3 = 4 \pi r^2 h and so h=9r.
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    (Original post by sophie7194)
    does anyone understand this question and could possibly help?
    it is:
    'a sphere and a cylinder have equal volumes.
    the sphere has radius 3r. the cylinder has radius 2r and height h.
    find h in terms of r'.

    i'm so confused could someone possibly attempt to explain it?
    You know the formulae for the volumes

    V_{sphere} = \frac{4}{3} \pi r^3
    V_{cylinder} = \pi r^2 h

    the question has stated that they are equal so we set V_{cylinder}=V_{sphere}

    we then just rearrange to make it in the form h=stuff
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    1)Use Vol of sphere formula and plug in r = 3r
    2)Use Vol of cylinder formula and plug r =2r
    3)After finding their volumes' in terms of h and r in steps one and two, equate them together as their volumes are equal
    4) Once you equate them together you can work with the equation till you set it equal to h.
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    (Original post by Leicester City)
    You absolute dumb ****. Use the formulae pages in your paper! They're practically giving you the answers you dumbo.
    chill out lol
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    (Original post by Leicester City)
    You absolute dumb ****. Use the formulae pages in your paper! They're practically giving you the answers you dumbo.
    We should really make downvotes a thing on this forum...
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    (Original post by Leicester City)
    You absolute dumb ****. Use the formulae pages in your paper! They're practically giving you the answers you dumbo.

    We should really make downvotes a thing on this forum...
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    (Original post by leicester city)
    you absolute dumb ****. Use the formulae pages in your paper! They're practically giving you the answers you dumbo.

    i'm going to cry laugh when u post a thread tomorrow about ur paper having a manufacturing problem and they missed out the formula page and no one helped you.
 
 
 
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