Question

How do you find the area of a circle with radius $ 4\;inches $ ?

Answer 1

Hint: To approach this kind question, you have to recall the formula of the shape which you are required to find the area. In this question you are required to find the area of the circle. So first try to recall the formula of the area of the circle. Formula of area of circle is equal to $ \pi {r^2} $ . This question is formula based, so try to memorize it.

Complete step-by-step answer:
Let's solve this problem.
Radius of the given circle $ r = 4\;inches $
As we know that the formula for area of circle $ = \pi {r^2} $
Also, we know that the value of $ \pi = \dfrac{{22}}{7} $ or $ \pi = 3.14 $ . We will be using $ \pi = \dfrac{{22}}{7} $
So, area of the circle $ = \dfrac{{22}}{7} \times 4\;inches \times 4\;inches $ ( $ \because $ radius $ r = 4\;inches $ )
Area of the circle $ = \dfrac{{22}}{7} \times 16\;inche{s^2} $
By multiplying $ 22 \times 16 $ , we get $ 352 $
Area of the circle $ = \dfrac{{352}}{7}inche{s^2} $
Now you leave your till this also or if you want your answer in decimal divide it by $ 7 $ .
Area of the circle $ = 50.28\;inche{s^2} $
So the area of the circle with radius $ 4\;inches $ is equal to $ \dfrac{{352}}{7}\;inche{s^2} $
So, the correct answer is “ $ \dfrac{{352}}{7}\;inche{s^2} $ ”.

Note: These are some of the precautions that are to be taken while solving this type of question. First your final answer should be with units. This is one of the common types of errors which students make. Second unit of area is always squared term i.e., $ inche{s^2} $ . When you are writing your final solution decimal values after two places values can be ignored. Mentioning not units in your final solutions can lead to deduction of marks.