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Question
The length of a rectangle is three times its breadth. If the area of the rectangle is 1875 sq. cm, find its perimeter.
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Solution
Let the breadth of a rectangle = x
and the length of a rectangle = 3x
∴ Area of the rectangle = l × b
⇒ 1875 cm2 = x × 3x
⇒ 3x2 = 1875
⇒ x2 = `1875/3`
⇒ x = `sqrt 625`
⇒ x = 25 cm
∴ Breadth of a rectangle = 25 cm
and legnth of a rectangle = 3 × 25 cm = 75 cm
Now, perimeter of a rectangle = 2 (l + b)
= 2 (75 + 25) cm
= 2 × 100 cm = 200 cm
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