Question

The pillars of an apartment are made in the cylindrical shape. If each pillar has a circular base of radius 40 cm and height 20 m, then how much concrete would be required to build 7 such pillars?

• A. 7040
• B. 70.4
• C. 704
• D. 7.04

Answer 1

The correct option is B

70.4

Radius of base of cylinder = 40 cm = 0.4m
Height of cylinder = 20m
Volume of single cylinder $=\pi r^{2}h=\frac{22}{7}\times {0.4}^2\times 20$
$=\frac{704}{70}{m}^3$

Thus, volume of 7 such pillars =

$\frac{704}{70}\times 7$ =

$70.4m^3$