NCERT Solutions for Class 6 Maths Chapter 10 Exercise 10.2
NCERT Solutions for Class 6 Maths Chapter 10 Exercise 10.2 (Ex. 10.2) Mensuration in Hindi and English Medium updated for academic session 2020-2021 free. All the solutions are given in PDF format as well as videos.Practice all the question answers according to your convenience whether through text solutions or videos solutions. In class 6 math exercise 10.2 we will learn how to find the area of any figure by counting the squares.
Class 6 Maths Chapter 10 Exercise 10.2 Solution
|Exercise: 10.2||PDF and Videos Solutions|
CBSE NCERT Class 6 Maths Chapter 10 Exercise 10.2 Solution in Hindi and English Medium
Class 6 Maths Chapter 10 Exercise 10.2 Solution in Videos
Perimeter of a Square
We know that all the sides of a square are equal.
If we denote the length of each side of the square by s, then its perimeter is given by
P = (s + s + s + s) = 4s.
The perimeter of a square of side s is given by P = 4s.
If the perimeter P of a square is known, then its side s can be found easily.
Perimeter = 4 × side
Thus, side = ¼ × Perimeter
A rectangular field is 45 m long and 32 m wide. Find its perimeter.
Length of the field = 45 m
Breadth of the field = 32 m
So, Perimeter of the field = 2 (length + breadth)
= 2 (45 + 32) m = 2 × 77 m
= 154 m
Concept of Area of close surface
The measure of the amount of surface enclosed by a figure is called its area.
Comparison of Areas
When the given surfaces are of the same shape, we compare them by placing one over the other.
Standard Units of Area
The area of a small figure is measured in square millimetres or square centimetres The bigger area is measured in square metres. Some examples given below:
(i) The area of a square of side 1 mm is 1 square millimetre, written as 1 square mm or 1 mm².
(ii) The area of a square of side 1 cm is 1 square centimetre, written as 1 square cm or 1 cm².
(iii) The area of a square of side 1 metre is 1 square metre, written as 1 square m or 1 m².
Length and breadth of a rectangular field are in the ratio 3 :2. If perimeter of the field is 70 m, then find its length and breadth in metre.
Let the length is 3x and the breadth is 2x.
We know that, P = 2 (l + b)
So, 70 m = 2(3x + 2x)
or, 70 m = 2 × 5x
x = 70/10 = 7 m
so, length = 3x
= 3 × 7 m
= 21 m and breadth = 2x
Where do we use perimeter and area in real life?
Uses of perimeter and area in daily life
(i) Fencing off an area to plot a crop. Since fences cost money for a given area you would want to minimize the perimeter.
(ii) Planning the construction of a house.
(iii) Building a barn with box stalls for horses.
(iv) Make Wooden furniture.
(v) Building a swimming pool.
How does perimeter relate to area?
The perimeter is the sum of all the side lengths of a shape. The area is the amount of two dimensional space a shape occupies.
Find the cost of fencing a square of the side 24 cm at the rate of Rs 4.50 per metre.
Side of the square = 24 cm
So, Perimeter of the square = 4 × side
= 4 × 24 cm = 96 cm
So, cost of fencing the square = Rs. (4.50 × 96)
= Rs. 432.
To fence a rectangular field, 260 m long wire is required. Find the length of the field if its breadth is 55 m.
Length of wire to fence the field = 260 m
= Perimeter of the field
So, Length of the field = perimeter – breadth
= ( ½ × 260 – 55) m = (130 – 55) m = 75 m