The radius of the base of a cylindrical drum is 40cm and its height is 70cm.How many litre of water can it hold (π=22 by or upon 7; 1000 cubic cm=1 litre)

Question

The radius of the base of a cylindrical drum is 40cm and its height is 70cm.How many litre of water can it hold (π=22 by or upon 7; 1000 cubic cm=1 litre)

Answer 1

Pi is NOT 22/7. It's approximately 3.141592654; if you use 22/7 you are GUARANTEEING that the result is not precise enough.

 

Just go ahead and calculate Volume using V = pi(radius²)(height).

 

I do note that h = 70 cm, so the use of 22/7 will cause the 7 denominator to cancel into the 70 height. Consequently the problem has been rigged so that you will get an integer answer. A very bad practice, in this world where calculators are ubiquitous.  To get # of liters, just shift the decimal point of the answer 3 PLACES TOWARD THE LEFT.