Question

The diameter of a closed cylinder is 21 cm and height is 10 cm. Find the total surface area of the cylinder.

Answer 1

Answer:

1353

Step-by-step explanation:

Surface area of the cylinder = 2πrh+2πr^2

=> 2π ( 10.5)(10) + 2π ( 10.5 )^2

=> 2π ( 105 ) + 2π (110.25)

=> 2π ( 105 + 110.25 ) [take 2π as common ]

=> 2π ( 215.25 )

=> 430.5π

=> 430.5 ( 22/7) [ value of π = 22/7 ]

=> 1353

Note: we can substitute π = 22/7 in the begining also.