Question

Find the circumference of the circle having radius 7 cm.

Answer 1

Hint: First of all, draw the diagram of the circle with radius 7 cm which will give us an idea of what we have to find. To calculate circumference of a circle, we multiply the radius of the circle with \[2\pi \]. So, use this concept to reach the solution of the given solution.

Complete step-by-step answer:
Given radius of the circle \[r = 7{\text{ cm}}\]
The diagram for the given circle is shown as in the below figure:

We know that the circumference of the circle with radius \[r\] is given by \[C = 2\pi r\].
So, circumference of the given circle is
\[\begin{gathered}
   \Rightarrow C = 2\pi \left( 7 \right) \\
   \Rightarrow C = 2 \times \dfrac{{22}}{7} \times 7{\text{ }}\left[ {\because \pi = \dfrac{{22}}{7}} \right] \\
   \Rightarrow C = 2 \times 22 \\
  \therefore C = 44{\text{ cm}} \\
\end{gathered} \]
Thus, circumference of the given circle is 44 cm.

Note: The circumference of a circle is defined as the linear distance around it. In other words, if a circle is opened to form a straight line then the length of that line will be the circle's circumference. Here we have taken the value of \[\pi \] as \[\dfrac{{22}}{7}\].