Question

The curved surface area of a right circular cylinder of height 21 cm is 957 cm/2 find in the diameter of the base of a cylinder

Answer 1

Given :-
C.S.A of cylinder = 957cm²
height = 21 cm


C.S.A = 957

=> 2πrh = 957

=> 2×22/7×r×21 = 957

=> 132×r = 957

=> r = 957÷132

=> r = 7.25

radius of the cylinder = 7.25cm


Diameter = 2r = 2×7.25 = 14.5 cm



Hope it helps.

Answer 2

Hi there !!

Given,
Curved surface area of the cylinder = 957cm²
Height = 21cm

Let the radius be r ,
diameter = 2r

We know,
lateral surface area = 2πrh

$957 = 2 \times \frac{22}{7} \times r \times 21$


$\frac{957 \times 7}{2 \times 22 \times 21} = r$
r = 7.25cm

Diameter = 2×r

= 2 × 7.25cm = 14.5cm

Thus,
the diameter is 14.5cm