Question

find the volume of the cone with circumference of base equal to 86cm and height 80cm.​

Answer 1

Answer:

Given, Circumference = 86cm

Height = 80cm

As C = 86cm,

2πr = 86cm

=> r = 86/2π

=> r = 43/π

Volume = πr²h/3

=> V = π(43/π)(43/π)(80)/3

=> V ≈ 15694.8cm³

Answer 2

The volume of cone is $15688.48\ cm^{2}$.

Step-by-step explanation:

In the question

circumference of base = 86 cm

height = 80 cm

We have to find the volume of cone. In this case first of all, we need to find the radius.

Let the radius of cone be x.

We know that,

circumference of base = 2πr

86 = 2πr

$\frac{86}{2} = \pi\ r$

$\frac{43}{\pi} = r$

∴ $r = \frac{43}{\pi}\ cm$

Now,

Volume of cone = $\frac{1}{3}\pi r^{2}h$

                           = $\frac{1}{3}\times\pi\times\frac{43}{\pi }\times\frac{43}{\pi }\times80$

                           = $\frac{1}{3}\times43\times{43}\times\frac{7}{22}\times80$

                            = $15688.48\ cm^{2}$

Therefore, the volume of cone will be  $15688.48\ cm^{2}$.