Question

9. Find
(i) the lateral or curved surface area of a closed cylindrical petrol storage tank that is 4.2 m in diameter and 4.5 m high.
(i) how much steel was actually used, if 1/12 of the steel actually used was wasted in
making the tank.
​

Answer 1

Step-by-step explanation:

we know that TSA of cylinder = 2^22/7^r^(r+h)

here'

diameter=4.2 means radius=2.1=21/10

hieght=4.5

therefore,2^22/7^21/10^(21/10+4.5) ( 4.5=45/10)

=66/5^(21/10+45/10)

=66/5^66/10

= 4356/50

=217800m sq. (^ = x)