NCERT Solutions for Class 7 Maths Chapter 11 Perimeter and Area

NCERT Solutions for Class 7 Maths Chapter 11 Perimeter and Area: Perimeter is the distance around a closed figure and area is the space occupied by a close figure. If we have to determine the length of the frame required to cover drawing in the shape of a rectangle of given length and breadth we will calculate the perimeter of the picture, that is Perimeter= 2(length + breadth). In the practical case, we will buy slightly higher than the required dimension since there may be cuts and joints requires for the frame. But if a question is asked we will calculate the perimeter.

In these NCERT Solutions for Class 7 Maths Chapter 11, we will study about the perimeters of rectangle triangle, parallelogram, and circles. To calculate the required amount of sheet to cover a rectangular window we will consider the area of the window. If the length of the window is l and breadth is b then area of the sheet required= area of window=lb. In NCERT Solutions for Class 7 Maths, we will also study the area of rectangle, triangle, parallelogram, and circles. While doing the problems of NCERT Solutions for Class 7 Maths Chapter 11 Perimeter and Area be careful about units are given. Convert all the given values to a common unit and do the problems.

The concept of Area of a triangle is given in NCERT Solutions for Class 7 Maths Chapter 11 Perimeter and area:

Area of a triangle: if the base length and height of a triangle are known is given by

$Area=\frac{1}{2}base\times height$

The perimeter of the triangle will be equal to the sum the sides of the triangle

Q) Calculate the area and perimeter of a triangle with base length =6cm and height = 4cm as shown in the below figure.

$\\Area=\frac{1}{2}base\times height\\=\frac{1}{2}6\times4=12cm^2$

Perimeter = sum of the sides = 5+6+5=16 cm

Circumference and Area of Circles is also mentioned in NCERT Solutions for Grade 7 Maths Chapter 11

If r is the radius of the circle then

$Area=\pi r^2$

$Circumference \of\ circle=2\pi r$

Q) Calculate the area and circumference of a protractor of diameter 7 cm as shown in figure

The radius of the protractor is half of its diameter = 3.5 cm

Circumference = Circumference of semicircular part + diameter

$=\pi r+7=\frac{22}{7}\times3.5+7= 18cm$

$\\area=\pi r^2=\pi r\times r\\=\frac{22}{7}\times3.5\times3.5=38.5cm^2$

Another concept mentioned in the NCERT Solutions for Class 7 Maths Chapter 11 is Area of Parallelogram

Area of a parallelogram: is the product of base length and height. For a parallelogram with base length b and height h

area=bh

The main topics of the NCERT Solutions for Class 7 Maths Chapter 11 Perimeter and Area are:

11.1 Introduction

11.2 Squares And Rectangles

11.2.1 Triangles As Parts Of Rectangles

11.2.2 Generalising For Other Congruent Parts Of Rectangles

11.3 Area Of A Parallelogram

11.4 Area Of A Triangle

11.5 Circles

11.5.1 Circumference Of A Circle

11.5.2 Area Of Circle

11.6 Conversion Of Units

11.7 Applications

NCERT Solutions for Class 7 Maths - Chapter-wise

 Chapter No. Chapter Name Chapter 1 Integers Chapter 2 Fractions and Decimals Chapter 3 Data Handling Chapter 4 Simple Equations Chapter 5 Lines and Angles Chapter 6 The Triangle and its Properties Chapter 7 Congruence of Triangles Chapter 8 Comparing Quantities Chapter 9 Rational Numbers Chapter 10 Practical Geometry Chapter 12 Algebraic Expressions Chapter 13 Exponents and Powers Chapter 14 Symmetry