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    I need help with finding the Surface area & volume of shapes my teacher gives me which are really complex.

    Their are like rectangular prisms with a cylinder stuck on top and bits cut off and weird combined shapes we have to find the volume and surface area of, some of them even have circles drawn on.

    I know the basics:

    length x width x height = volume
    pi r squared = area of a circle

    argh im confused. this is from the 'mathematics for technicians' unit for BTEC level 2 first engineering.
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    Well the volume of a sphere is (pi x d), which might also be useful, and basically all you need to do is break up the complex shapes into their smaller pieces. For example, if you had to find the volume of a cube with a cylinder attached, you would first work out:

    The volume of the cube.

    Then the area of one of the end circles of the cylinder.
    Then multiply that by the length of the cylinder to find the volume.
    Then add that onto the volume of the cube.

    It's really quite simple as long as you break up the tasks into the individual shapes that make them up.

    Hope that helps a bit?
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    (Original post by carrotstar)
    Well the volume of a sphere is (pi x d), which might also be useful, and basically all you need to do is break up the complex shapes into their smaller pieces. For example, if you had to find the volume of a cube with a cylinder attached, you would first work out:

    The volume of the cube.

    Then the area of one of the end circles of the cylinder.
    Then multiply that by the length of the cylinder to find the volume.
    Then add that onto the volume of the cube.

    It's really quite simple as long as you break up the tasks into the individual shapes that make them up.

    Hope that helps a bit?
    Hey carrotstar - you say "volume of sphere is (pi x d)" - what do you mean? Do you mean "volume of sphere = pi times d; where pi=3.142... and d=diameter"? If so then I am sorry to say that you are wrong! The volume of a sphere = 4.PI.R(cubed)/3" where the . represents multiply, R is the radius and PI=3.142.....
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    oh **** sorry :/ well it sounds like you know your stuff, in which case I'm not sure how you're confused... well this is awkward :L
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    (Original post by AM1R)
    I need help with finding the Surface area & volume of shapes my teacher gives me which are really complex.

    Their are like rectangular prisms with a cylinder stuck on top and bits cut off and weird combined shapes we have to find the volume and surface area of, some of them even have circles drawn on.

    I know the basics:

    length x width x height = volume
    pi r squared = area of a circle

    argh im confused. this is from the 'mathematics for technicians' unit for BTEC level 2 first engineering.
    pi*r^2h = Volume of a cylinder.
    Cone = 1/3(pir^2h)
    In general area of a prism = Face area x length
 
 
 
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