Question

The volume of a cylinder is 6358 cm3, and its height is 28 cm. Find its radius and the curved surface area​

Answer 1

Answer:

radius=8.5  , curved surface area​ =1494.6 cm²

Step-by-step explanation:

=πr²h = 6358

=3.14 X r² X 28 =6358

=r² = 6358/ (28 X 3.14)

= r²=6358/ 88

=r²=72.25

r= 8.5

curved surface area

=2πrh

=2 X 3.14 X 8.5 X 28

=1494.6 cm²

Answer 2

S O L U T I O N :

$\underline{\bf{Given\::}}$

• The volume of a cylinder, (V) = 6358 cm³
• Height of cylinder, (h) = 28 cm

$\underline{\bf{Explanation\::}}$

As we know that formula of the volume of cylinder;

$\boxed{\bf{Volume = \pi r^{2} h\:\:\:(cubic\:unit)}}$

A/q

$\mapsto\tt{Volume\:of\:cylinder = \pi r^{2} h}$

$\mapsto\tt{6358 = \dfrac{22}{7} \times r^{2} \times 28}$

$\mapsto\tt{6358 = \dfrac{22}{\cancel{7}} \times r^{2} \times \cancel{28}}$

$\mapsto\tt{6358 = 22 \times r^{2} \times 4}$

$\mapsto\tt{6358 = 88 \times r^{2} }$

$\mapsto\tt{ r^{2} = \cancel{6358/88}}$

$\mapsto\tt{ r^{2} = 72.25}$

$\mapsto\tt{ r = \sqrt{72.25}}$

$\mapsto\bf{r = 8.5\:cm}$

Now,

Using formula of the curved surface area of cylinder;

$\boxed{\bf{C.S.A = 2\pi rh\:\:(sq.unit)}}$

$\mapsto\tt{C.S.A = 2 \times \dfrac{22}{7} \times 8.5 \times 28}$

$\mapsto\tt{C.S.A = 2 \times \dfrac{22}{\cancel{7}} \times 8.5 \times \cancel{28}}$

$\mapsto\tt{C.S.A = (2 \times 22 \times 8.5 \times 4)}$

$\mapsto\bf{C.S.A = 1496\:cm^{2}}$

Thus,

The radius of cylinder & C.S.A will be 8.5 cm & 1496 cm² .