FIND THE PERIMETER OF THE GIVEN SHAPE

Find the perimeter of each figure :

Problem 1 :

Solution :

By observing the figure, it is a triangle.

Perimeter of the triangle P = a + b + c

Here a = 14 in, b = 12 in and c = 18 in

= 14 + 12 + 18

Perimeter P = 44 in

Problem 2 :

Solution :

By observing the figure, it is a triangle.

Perimeter of the triangle P = a + b + c

Here a = 13 cm, b = 12 cm and c = 5 cm

= 5 + 13 + 12

Perimeter P = 30 cm

Problem 3 :

Solution :

By observing the figure, it is a rectangle.

Perimeter of the rectangle P = 2(l + b)

Here l = 7m, and b = 21m

= 2(7 + 21)

= 2(28)

Perimeter P = 56 m

Problem 4 :

Solution :

By observing the figure, it is a rectangle.

Perimeter of the rectangle P= 2(l + b)

Here l = 14 ft, and b = 19 ft

= 2(19 + 14)

= 2(33)

Perimeter P = 66 ft

Problem 5 :

Solution :

By observing the figure, it is a irregular shape.

Perimeter P = Sum of all the sides

= a + b + c + d

Here a = 19 yd, b = 18 yd, c = 16 yd, and d = 18 yd

= 19 + 18 + 16 + 18

Perimeter P = 71 yd

Problem 6 :

Solution :

By observing the figure, it is a trapezoid.

Perimeter of the trapezoid P = a + b + c + d

Here a = 17 m, b = 24 m, c = 17 m, and d = 29 m

= 17 + 24 + 17 + 29

Perimeter P = 87 m

Problem 7 :

Solution :

By observing the figure, it is a irregular shape.

Perimeter P = Sum of all the sides

 = a + b + c + d + e + f

Here a = 4ft, b = 24 ft, c = 7 ft, d = 19 ft, e = 3 ft, and f = 5 ft

= 24 + 7 + 19 + 3 + 5 +4

Perimeter P = 62 ft

Problem 8 :

Solution :

By observing the figure, it is a irregular shape.

Perimeter P = Sum of all the sides

 = a + b + c + d + e

Here a = 25 in, b = 10 in, c = 14 in, d = 7 in, e = 11 in

= 25 + 10 + 14 + 7 + 11

= 67 in 

Problem 9 :

Find the perimeter of the square whose side is 2.5 cm.

Solution :

Side length of square = 2.5 cm

Perimeter of square = 4(side)

= 4(2.5)

= 10 cm

So, the perimeter of the square is 10 cm.

Problem 10 :

What will be the perimeter of a rectangle whose length is 2 m and breadth is 1.5 m ?

Solution :

Perimeter of rectangle = 2(length + width)

Length = 2 m and breadth = 1.5 m

= 2(2 + 1.5)

= 2(3.5)

= 7 m

So, the perimeter of the rectangle is 7 m.

Problem 11 :

Two squares of side 4 cm each are joined together to make a new figure. What is the figure called?

Solution :

Side length each square = 4 cm

When two squares are joined together, length of rectangle = 4 + 4 ==> 8 m

Width = 4 cm

Perimeter of rectangle = 2(8 + 4)

= 2 (12)

= 24 cm

So, the perimeter of the rectangle is 24 cm.

Problem 12 :

Find the perimeter of an equilateral triangle of side 9 cm

Solution :

Perimeter of equilateral triangle = 3(side)

Side length = 9 cm

= 3(9)

= 27 cm

Problem 13 :

Find the perimeter of a triangle of sides 3 cm, 4 cm and 5 cm.

Solution :

Let a, b and c are the side lengths of triangle.

a = 3 cm, b = 4 cm and c = 5 cm

Perimeter of triangle = 3 + 4 + 5

= 12 cm

Problem 14 :

Find the perimeter of an isosceles triangle whose equal sides are 8 cm each and third side is of 6 cm.

Solution :

Let a, b and c be three sides of triangle.

Here a and b be the equa l sides.

a = 8 cm = b and c = 6 cm

Perimeter of triangle = a + b + c

= 8 + 8 + 6

= 22 cm

Problem 15 :

Two sides of a triangle are 12 cm and 14 cm. If the perimeter of the triangle is 36 cm, find the third side.

Solution :

Let x be the third side of the triangle. The other sides are 12 cm and 14 cm.

Perimeter of triangle = 36 cm

12 + 14 + x = 36

26 + x = 36

x = 36 - 26

x = 10 cm

So, the third side is 10 cm.