Question

The length of a wall is 6m and the breadth is 4 m.There is a door of length 3m and breadth 1.5m fitted in the wall.Find the cost of whitewashing the wall at Rs 30 per m².​

Answer 1

Answer :

• Rs.585 is the cost of whitewashing the wall at Rs.30 per m².

Given :

• The length of a wall is 6m and the breadth is 4m
• There is a door of length 3m and breadth 1.5m fitted in the wall.

To Find :

• The cost of whitewashing the wall at Rs 30 per m²

Solution :

• Area of whitewashing = Area of wall - Area of Door

First we need to find the Area of wall :

Given,

• Length of wall is 6m
• Breadth of wall is 4m

We know that

• Area of wall = l × b

Where,

• l is length of wall
• b is breadth of wall

Substituting the value :

↦ Area of wall = 6 × 4

↦ Area of wall = 24

Area of wall is 24m².

Now , We need to find the Area of Door:

Given

• Length of door is 3m
• Breadth of door is 1.5m

We know that

• Area of door = l × b

Where,

• l is length of door
• b is breadth of door

↦ Area of door = length × breadth

↦ Area of door = 3 × 1.5

↦ Area of door = 4.5m²

Area of door is 4.5m².

Now,

• Area of whitewashing = Area of wall - Area of door

↦ Area of whitewashing = 24 - 4.5

↦ Area of whitewashing = 19.5m²

Now,Given

• Cost of whitewashing 1m² of wall = 30m²
• Cost of white washing 19.5m² of wall = 30 × 19.5

↦ 30 × 19.5

↦ 30 × 195/10

↦ 3 × 195

↦ 585 Rs

Rs.585 is the cost of whitewashing the wall at Rs.30 per m².