Question

in the village there a cylindercial well who radius is 2.8m h=3/5m how much water can it hold a person need 70 litere of water in a village for how many person the waterwill suffient​

Answer 1

CORRECT QUESTION :-

In a village there is a cylindercial well who radius is 2.8m h=3/5m.

(i)How much water can it hold?

(ii) One person need 70 litres of water then for how many persons is the water sufficient ?

GIVEN :-

• Radius and height of cylindrical well are 2.8m and 3/5m
• Number of litres of water needed by one person is 70 litres

TO FIND :-

• Quantity of water that can be hold by the cylindrical well and the number of persons get the required 70 litres of water

SOLUTION :-

Number of litres that can be hold by the cylindrical well = Volume of the cylindrical well

$\large\rm\bold{\boxed{Volume\:of\:cylinder\:=\:\pi\:r^2h}}$

Where ,

• r is Radius of cylinder
• h is height of cylinder

We are given that ,

Radius of cylindrical well = 2.8 m

Height of cylindrical well = 3/5 m = 0.6m

$\large\rm{\rightarrow{Volume\:of\:well\:=\:\frac{22(2.8)^2(0.6)}{7}}}$

$\large\rm{\rightarrow{Volume\:of\:well\:=\:1.12(0.6)(22)}}$

$\large\rm{\rightarrow{Volume\:of\:well\:=\:14.784\:m^3}}$

$\large\rm\bold{\boxed{1\:m^3\:=\:1000\:litres}}$

$\large\rm{\rightarrow{Volume\:of\:well\:=\:14.784\times\:1000\:litres}}$

$\large\rm{\rightarrow{Volume\:of\:well\:=\:14784\:litres}}$

∴ The water that can be hold by the cylindrical well is 14784 litres

By unitary method ,

If 70 litres ---------> 1 person

14,784 litres ---------> 'x' (Let)

$\large\rm{\rightarrow{x\:=\:\frac{1}{70}\times\:14784}}$

$\large\rm{\rightarrow{x\:=\:\frac{14784}{70}\:=\:211}}$

∴ 211 persons can get 70 litres of water from the cylindrical well which can hold 14,784 litres

$\huge\rm{\underline{\green{Additional\:Info:-}}}$

❃ Curved surface area (CSA) of cylinder is given by ,

$\large\rm\bold{\boxed{CSA\:=\:2\pi\:rh}}$

Where ,

• r is Radius of cylinder
• h is Height of cylinder

❃ Total surface area (TSA) of cylinder is given by ,

$\large\rm\bold{\boxed{TSA\:=\:2\pi\:r(r+h)}}$

Where ,

• r is Radius of cylinder
• h is height of cylinder