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example 2: Find the cost of fencing a rectangular plot, 138 m long and 72 m wide at the
rate of `48 per metre.
Solution: Length of the plot = 138 m and breadth of the plot = 72 m

Since, perimeter of the plot = 2 (Length + Breadth)
Note
= 2 (138 + 72) m While calculating

= 2 × 210 m the perimeter of the
length and breadth
= 420 m must have same units.

The cost of fencing the plot is `48 per metre.
So, the total cost of fencing = `(420 × 48) = `20,160

Hence, the cost of fencing the plot is `20,160.
example 3: Suyash jogs 6 rounds around a park everyday in the morning. If the park is 156
m long and 112 m wide. How much distance does he cover?

Solution: Length of the park = 156 m and breadth of the park = 112 m
Since, perimeter of the park = 2 (Length + Breadth)

= 2 (156 + 112) m
= 2 × 268 m

= 536 m
Distance covered by Suyash in 1 round = 536 m

Total distance covered by Suyash in 6 rounds = (6 × 536) m = 3216 m
Thus, Suyash covers 3216 m in 6 rounds. 76 cm

example 4: The perimeter of a rectangular field is 182 m and its length
is 76 m. Find its breadth. ?
Solution: Perimeter of the rectangular field = 2 (Length + Breadth)

182 = 2 (76 + Breadth) ( Perimeter = 182 m given)
182 ÷ 2 = 76 + Breadth

91 = 76 + Breadth
So, the breadth of the rectangle = 91 m – 76 m = 15 m
Thus, the breadth of the rectangular field is 15 m.

perimeter of a Square

We know that a square is a 4-sided polygon whose all four sides are of equal length.
In the given figure, ABCD is a square.
A D
So, perimeter of a square = AB + BC + CD + DA
= AB + AB + AB + AB (Since, AB = BC = CD = DA)

= 4 × AB
Hence, perimeter of a square = 4 × Side B C

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