Answer :

Given: Length of wall = 4.5 m

Breadth of the wall = 3.6 m

Length of the door = 2 m

Breadth of the door = 1 m

Area of the wall = l × b = 4.5 m × 3.6 m = 16.20\( m^2 \)

Area of the door = l × b = 2 m × 1 m = 2 \(m^2\)

\(\therefore \) Area of the wall to be white washed = Area of the wall – Area of the door

= 16.20 \(m^2 – 2 m^2= 14.20 m^2\)

Cost of white washing

= Rs. 14.20 × 20 = Rs. 284.00

Hence, the required area = 14.20\( m^2 \)and the required cost = Rs. 284

- Q.1 The length and the breadth of a rectangular piece of land are 500 m and 300 m respectively. Find (i) its area (ii) the cost of the land, if 1\( m^2 \) of the land costs Rs. 10,000
- Q.2 Find the area of a square park whose perimeter is 320 m.
- Q.3Find the breadth of a rectangular plot of land, if its area is 440\( m^2 \)and the length is 22 m. Also, find its perimeter.
- Q.4 The perimeter of a rectangular sheet is 100 cm. If the length is 35 cm, find its breadth. Also find the area.
- Q. 5 The area of a square park is same as of a rectangular park. If the side of the square park is 60 m and the length of the rectangular park is 90 m, find the breadth of the rectangular park.
- Q.6 A wire is in the shape of a rectangle. Its length is 40 cm and breadth is 22 cm. If the same wire is rebent in the shape of a square, what will be the measure of each side. Also find which shape encloses more area?
- Q.7 The perimeter of a rectangle is 130 cm. If the breadth of the rectangle is 30 cm, find its length. Also find the area of the rectangle.

- NCERT solutions for class 7 maths chapter 1 Integers
- NCERT solutions for class 7 maths chapter 2 Fractions and Decimals
- NCERT solutions for class 7 maths chapter 3 Data Handling
- NCERT solutions for class 7 maths chapter 4 Simple Equations
- NCERT solutions for class 7 maths chapter 5 Lines and Angles
- NCERT solutions for class 7 maths chapter 6 The Triangle and its Properties
- NCERT solutions for class 7 maths chapter 7 Congruence of Triangles
- NCERT solutions for class 7 maths chapter 8 Comparing Quantities
- NCERT solutions for class 7 maths chapter 9 Rational Numbers
- NCERT solutions for class 7 maths chapter 10 Practical Geometry
- NCERT solutions for class 7 maths chapter 11 Perimeter and Area
- NCERT solutions for class 7 maths chapter 12 Algebraic Expressions
- NCERT solutions for class 7 maths chapter 13 Exponents and Powers
- NCERT solutions for class 7 maths chapter 14 Symmetry
- NCERT solutions for class 7 maths chapter 15 Visualising Solid Shapes

- NCERT solutions for class 7 science chapter 1 Nutrition in Plants
- NCERT solutions for class 7 science chapter 2 Nutrition In Animals
- NCERT solutions for class 7 science chapter 3 Fibre to Fabric
- NCERT solutions for class 7 science chapter 4 Heat
- NCERT solutions for class 7 science chapter 5 Acids Bases and Salts
- NCERT solutions for class 7 science chapter 6 Physical and Chemical Changes
- NCERT solutions for class 7 science chapter 7 Weather, Climate and Adaptations of Animals to Climate
- NCERT solutions for class 7 science chapter 8 Winds, Storms and Cyclones
- NCERT solutions for class 7 science chapter 9 soil
- NCERT solutions for class 7 science chapter 10 Respiration in Organisms
- NCERT solutions for class 7 science chapter 11 Transportation in Animals and Plants
- NCERT solutions for class 7 science chapter 12 Reproduction In Plant
- NCERT solutions for class 7 science chapter 13 Motion and Time
- NCERT solutions for class 7 science chapter 14 Electric Current and Its Effects
- NCERT solutions for class 7 science chapter 15 Light
- NCERT solutions for class 7 science chapter 16 Water: A Precious Resource
- NCERT solutions for class 7 science chapter 17 Forests: Our Lifeline
- NCERT solutions for class 7 science chapter 18 Waste Water Story