Perimeter = Distance covered in 8 min. = ❨ 12000 x 8 ❩m = 1600 m. 60 Let length = 3x metres and breadth = 2x metres. Then, 2(3x + 2x) = 1600 or x = 160. ∴ Length = 480 m and Breadth = 320 m. ∴ Area = (480 x 320) m2 = 153600 m2
Area of square = 40 x 40 = 1600 sq.cm Given that the areas of Square and Rectangle are equal => Area of rectangle = 1600 Sq.cm We know that, Area of rectangle = L x B Given L = 64 cm Breadth of rectangle = 1600/64 = 25 cm Perimeter of the rectangle = 2(L + B) = 2(64+25) = 178 cm.
Let base = b and altitude = h Then, Area = b x h But New base = 110b / 100 = 11b / 10Let New altitude = HThen, Decrese = (h - 10h /11 )= h / 11? Required decrease per cent = (h/11) x (1 / h ) x 100 %= 91/11 %