Area Problems
Floor of a square room of side 10 m is to be completely covered with square tiles, each having length 50 cm. The smallest number of tiles needed is?
Area of square room = (10)2 = 100 sq m= 100 x (100)2 sq cm= 100 x 100 x 100 sq cmNow, area of tiles = (50)2 = 50 x 50 sq cm? Number of tiles needed = (Area of square room) / (Area of tile)= (100 x 100 x 100) / (50 x 50) = 400Hence, 400 tiles will be needed.
? 22/7 x r2 = 13.86 x 10000? r2 = (13.86 x 10000 x 7) / 22? r = 210 m ? Circumference = [2 x (22/7) x 210 ] m = 1320 m Cost of fencing = Rs. (1320 x 20)/100= Rs . 264
Let the radius of circular field = r m.Speed of person in m/s = 30/60 = 1/2m/sAccording to the question,[(2?r) /(1/2)] - [(2r)/(1/2)] = 30? 4?r - 4r = 30? [4 x (22/7) - 4]r =30? (125 - 4)r = 30 ? (8.5)r = 30? r = 30/8.5 = 3.5 m