Question

A window of length 1.5m and 0.5m is on the wall of length 4.5m and breadth 3.5m.Find the cost of white washing the wall if the rate of white washing the wall is ₹25 per square metre

Answer 1

Given

• Dimensions of a window :-
• Length of the window = 1.5 m
• Breadth of the window = 0.5 m
• Dimensions of a wall including the window :-
• Length of the wall including the window = 4.5 m
• Breadth of the wall including the window = 3.5 m
• Cost of whitewashing 1 m² of the wall including the window = ₹25

To find

• Cost of whitewashing the wall

Solution

Firstly, we will find the area of the window.

Using formula,

Area = l × b

where,

• l = length of the window
• b = breadth of the window

Substituting the the given values,

⟶ 1.5 × 0.5

⟶ 0.75 m²

• Area of the window = 0.75 m²

Now, we will find the area of the wall including the window.

Using formula,

Area = l × b

Substituting the the given values,

⟶ 4.5 × 3.5

⟶ 15.75 m²

Area of the wall including the window = 15.75 m²

Now, we will find the area of the wall.

Area of the wall = Area of the wall including the window - Area of the window

⟶ 15.75 - 0.75

⟶ 15 m²

• Area of the wall = 15 m²

Cost of whitewashing 1 m² of the wall = ₹25

Cost of whitewashing 15 m² of the wall = 25 × 15 = ₹375

Cost of whitewashing the wall = ₹375