The perimeter of a square field is 10 cm more than the

Solution

Let the width of the rectangle = x cm Then, 80% of x = 60 x = 60 × 100/80 = 75 cm Perimeter of the rectangle = 2 (length + width) = 2 × (60 + 75) = 270 cm Perimeter of the square = (270 + 10) = 280 cm The sides of the square = 280/4 = 70 cm The area of the square field without street = (70)² sq. cm = 4900 sq. cm   The area of the square field with street = (70 + 20)² sq. cm = 8100 sq. cm The area of the street = 8100 – 4900 = 3200 sq. cm The total cost of constructing the street = 3200 × 20 = Rs. 64000