Circumference of a Circle Practice

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Question 1

Given a circle with the radius of 8cm. Find the circumference of this circle. Take π as 3.14.

Answer

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Select and check your answer...

A. 30.24cm
B. 40.24cm
C. 50.24cm
D. 60.24cm

Step by Step Solution

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    Step 1

    The picture below shows the circle with the radius of 8cm.

    a circle with radius of 8cm
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    Step 2

    To calculate the circumference, we can use the following formula:

    formula for the circumference of a circle
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    Step 3

    The radius is given as 5cm. Hence, we can substitute r with 5. Similarly, we can substitute π with 3.14. After substituting these values, we can calculate for C:

    Calculating the circumference of a circle
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    Step 4

    Now, 50.24 only has meaning if we include the unit for it. Since the radius is in cm, the circumference will also be in cm. Hence:

    C = 50.24cm
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    Step 5

    Clearly, the answer is C.

    square root of 100 is 10