Question

If the diameter of the circle is $6cm$ , what will its radius be?

Answer 1

Hint: First, we need to know about the concept of the radius and diameter, so that we can simply solve the given problem using the information.
Diameter is the calculation of distance between two points on a circle passing through the circle. Hence the diameter of the circle is $2$ times its radius. Thus, we will make use of the relation to solve the given problem.

Complete step-by-step solution:
Since the given diameter of the circle is $6cm$ and we have to find its radius.
The diameter can be represented as $d = 6cm$
Now first of all let us understand the circle of the diameter and radius. So, a circle is the collection of all the points lying in a plane at a distance from the center point. The distance between the center and all the points on the circle is known as the radius.
Hence the distance between two points on the circle passing from the center is known as the diameter of the circle.
Therefore, the diameter is double in length to the radius, and hence we have the relation as $d = 2r$
Now divide both the sides with the number $2$ then we get $r = \dfrac{d}{2}$
Since we know that the diameter of the circle is $6cm$ and substituting the values we have $r = \dfrac{d}{2} \Rightarrow \dfrac{6}{2}cm$ and by the division operation we get $r = 3cm$ which is the required answer.

Note: To find the circumference of the circle, we can use the given two formulas.
If the diameter is given then we have $C = \pi \times d$ where C is the circumference.
If the radius is given then we have $C = 2\pi r$
Also, note that the value of the pie can be expressed as $\pi = 3.14$