Question

The diameter of the circle is $ 2 $ cm. What is the circumference?
A. $ 12.28 $ cm
B. $ 6.2 $ cm
C. $ 18.28 $ cm
D. $ 10.28 $ cm

Answer 1

Hint: Circumference of the circle is also known as the perimeter of the circle. It can also be defined as the arc length of the circle. Here we will use the standard formula to find the circumference and then simplifying the expression placing the given data.

Complete step-by-step answer:
Given that: diameter of the circle, $ d = 2cm $
Now, the circumference of the circle can be given by –
 $ C = \pi d $
Place the given values and $ \pi = 3.14 $ in the above expression-
 $ C = 3.14(2) $
Simplify the above expression finding the product of the terms –
 $ C = 6.28 $ cm
Hence, from the given multiple choices – the option B is the correct answer.
So, the correct answer is “Option B”.

Note: Circumference of the circle can also be calculated by using the formula $ 2\pi r $ where r is the radius of the circle. Diameter is twice that of radius. Know the correlation between the terms and equations. Be careful while simplifying the equation when the value is in decimal. You can calculate by placing hundred below the term and removing decimal points to remember its equivalent expression such as $ 3.14 = \dfrac{{314}}{{100}} $ . Do not forget to place the appropriate unit after the solution.