Let original radius be r.Then, according to the questions,? (r + 1)2 - ?r2 = 22? ? x [(r + 1)2 - r2] = 22? (22/7) x (r + 1 + r ) x (r + 1 - r) = 22? 2r + 1 = 7 ? 2r = 6 ? r = 6/2 = 3 cm
perimeter = total cost / cost per m = 10080 /20 = 504mside of the square = 504/4 = 126mbreadth of the pavement = 3mside of inner square = 126 - 6 = 120marea of the pavement = (126 x126) - (120 x 120) = 246 x 6 sq mcost of pavement = 246*6*50 = Rs. 73800
Area to the rectangular field = 12375/15 = 825 sq mAccording to the question, (L x B) = 825 [L = length and B = breadth]? L x 25 = 825 ? L = 825/25 = 33 m
Let Length = 5y meters and breadth = 3y meters.Then, perimeter = 2 x (5y + 3y ) m = 16y meters ...(i)But perimeter = Total Cost / Rate = 3000 / 7.50 m = 400 m ...(ii)from eqs. (i) and (ii)16y = 400? y = 25? Length - Breadth = (5 x 25 - 3 x 25 ) m = 2 x 25 m = 50 m