Thursday, January 16, 2014

POTW #15

5 comments:

  1. 4cm by 4cm is the square
    Pie (4cm*4cm)
    the area of the circle is 50.24 cm2
    50.24/4 = 12.56 cm2
    16 cm2 - 12.56 cm2 = 3.44cm2 is the shaded region

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  2. Hello.

    The answer I got was 3.44cm2. I got this by using the formula of finding the area of a circle (area = pie x square of the radius). But first, I had to find the dimensions of the square, which was L=4cm, W=4cm, this was also the radius of the circle. I knew this because the area of the square was 16cm2.

    area of the circle = pi (4x4)
    area of the circle = pi x 16

    shaded area = area of the square - 1/4 area of circle
    shaded area = 16 - 4 pi
    shaded area = 16 - 4 x 3.1416
    shaded area = 16 - 12.56
    shaded area = 3.44cm2

    -Rachel

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  3. Ello.

    I know that the square is 16 cm squared, which means that line AO and line OC are 4 cm. This makes 4 cm the radius.

    To find shaded area, I subtracted 16 cm squared by the area of the circle.

    Area of circle = Pi x radius^2 (3.14 x 4cm^2)
    =50.26 cm squared

    Then I divided the area by 4 since the region inside square OABC is 1/4 of a circle.

    50.26 / 4 = 12.56

    12.56 cm is the area of the non-shaded part of the square.
    Then I subtract 16 cm by 12.56 to find the area of the shaded part
    16 - 12.56 = 3.44 cm squared

    To wrap it up..:

    Area of Circle = 50.26 squared

    Non-Shaded region in square = 12.56 squared

    Square = 16 cm squared

    Shaded region in square = 3.44 squared.



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  4. All three of you nailed it! Great job!

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  5. nice guys! you obviously know your stuff... anyway of using 'distributive' property to even simplify the calculation process? =)

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