Question

if the diameter of a cylinder is 28cm and it's height is 20cm, then the total surface is

Answer 1

Find the radius:

Radius = Diameter ÷ 2

Radius = 28 ÷ 2 = 14 cm

Find the surface area:

Surface area  = 2πr² + 2πrh

Surface area = 2π (14)² + 2π(14)(20) = 2992 cm²

Answer: The total surface area is 2992 cm²

Answer 2

$\huge {\bold {Solutions:-}}$


We have,

Diameter = 28 cm
Height = 20 cm


Radius = 28/2 = 14 cm


Now,

Total surface area = (2πr² + 2πrh) sq. unit

= (2×22/7 × 14² + 2×22/7×14×20) cm²

= 2992 cm²


Hence,

$\underline {\bold {Total~surface~area~of~cylinder}}$
$\underline {\bold { =~2992~cm^2}}$