Question

Find the diameter of a circle whose circumference is 77​

Answer 1

We are given that the circumference of a circle is 77 units and we need to find it's diameter . But let's recall that for any Circle with radius r , the circumference is given by 2πr . And diameter is double of radius i.e d = 2r , so we can write the circumference as 2r(π) i.e dπ . So , now here

`{:\implies \quad \sf d\pi =77}`

`{:\implies \quad \sf d* (22)/(7)=77}`

`{:\implies \quad \sf d=(77* 7)/(22)}`

`{:\implies \quad \sf d=\frac{\cancel{11}* 7* 7}{\cancel{11}* 2}}`

`{:\implies \quad \sf d=(49)/(2)}`

`{:\implies \quad \bf \therefore \quad \underline{\underline{Diameter=24.5\:\: units}}}`