Question

The diameter of a cylinder is 28 cm and its height is 20 cm. The total surface area of the cylinder is ______.

विकल्प

• 2993 cm²

• 2992 cm²

• 2292 cm²

• 2229 cm²

Answer 1

The diameter of a cylinder is 28 cm and its height is 20 cm. The total surface area of the cylinder is 2992 cm².

Explanation:

The total surface area of the cylinder = 2πr + 2r² 

= 2π(h + r)

`= [2xx22/7xx14xx(20+14)]"cm"^2`           `["d" = 28  cm => "r" = 28/2 "cm" = 14  "cm" ]`

`= 20944/7  "cm"^2`

= 2992 cm²