By definition, the volume of a cone is given by:

Where,
r: radius of the circular base
h: height of the cone
Let's define a variable:
x: diameter of the base
We have then that the radio is:

The height is:

Substituting values:

Rewriting:
Answer:
An expression that represents the volume of the cone, in cubic units is:
So basically ...
You convert the rupees in paisas. One rupee is equal to one hundred paisas, so ...
280 × 100 = 28,000
And then we divide,
28,000 ÷ 14 = 2000
The post office sold 2000 stamps!
Hope this helped! :)
-1.7×-6 is the answer. Hope this helps.