Question

The height of a cone is 21 cm. Find the area of the base if the slant height is 28 cm.

Answer 1

In a cone, the vertical height ‘h’ is given as 21 cm and the slant height ‘l’ is given as 28 cm, and the area of the base is asked. The base area is given as

Base area =

To find the base radius ‘r’ we use the relation between r, l and h.

We know that in a cone

=

=

=

Therefore the base radius is, r = cm.

Now, let us substitute the value of r in the formula for area of the base.

Base Area =

=

=

= 1078

Hence, the base area of the cone with the specified dimensions is.