Q75 of 131 Page 226

The perimeter of a rectangle is 40 m. Its length is four metres less than five times its breadth. Find the area of the rectangle.

Let breadth of the rectangle be x.


Then, length of the rectangle = 5x – 4


We know that perimeter of rectangle = 2 × (l + b)


40 = 2 × (x + 5x - 4)


40 = 2 × (6x - 4)


12x - 8 = 40


12x = 48


x = = 4


So, breadth of the rectangle = x = 4 m


Length of the rectangle = 5x – 4 = 5 × 4 – 4 = 20 – 4 = 16 m


Area of rectangle = l × b = 16 × 4 = 64 m2


Hence, area of rectangle = 64 m2


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