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Calculate the circumference and area of the circle whose diameter = 14.

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seedrasoso | Student, Grade 10 | eNoter

Posted August 2, 2010 at 7:45 AM via web

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Calculate the circumference and area of the circle whose diameter = 14.

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hala718 | High School Teacher | (Level 1) Educator Emeritus

Posted August 2, 2010 at 7:47 AM (Answer #1)

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We have the diameter d = 14

Then the radius of the circle (r) = d/2 = 7

The circumference (C) = 2*r*pi

                                    = 2*7*22/7

                                     = 44 unit>

The area (a) = Pi*r^2

                     = (22/7)*(7^2)

                     = 22*7

                     = 154 square unit.

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pohnpei397 | College Teacher | (Level 3) Distinguished Educator

Posted August 2, 2010 at 7:49 AM (Answer #2)

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The answer to this is that the area of the circle is 154 square units and the circumference is 44.  Here is how to find this answer.

We know that the area of a circle is found by the equation

area = pi*r2 where r is the radius.  The radius here is 7 because that is half of the diameter.

So

area = 3.14*7^2

area = 3.14*49

area = 153.86 or 154

We know that the circumference of a circle is found by the equation

circumference = 2*pi*r

So circumference = 2*3.14*7 = 43.96 or 44

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krishna-agrawala | College Teacher | Valedictorian

Posted August 2, 2010 at 8:15 AM (Answer #3)

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Circumference of a circle = pi*diameter

Substituting the given value of diameter, and value of pi (22/7) in above equation:

Circumference = (22/7)*14 = 44

Area of a circle = [pi*(diameter)^2]/4

Substituting the given value of diameter, and value of pi in above equation:

Area = (22/7)(14^2)/4 = 154

Answer:

Circumference = 44

Area = 154

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