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.
Circular piece is 4 x 11 = 44 cm long, Then Circumference of circle is given by, 44 = pi x D, where D is the diameter D = 44 / pi Take pi = 22 / 7, then D = 44 / (22/7) = (44 x 7) / 22 D = 14 cm.
Area of equilateral triangle = ?3a2/4 = x ......(i)And perimeter = 3a = y ? a = y/3 ....(ii)Now, Putting the value of a from Eq. (ii) in Eq. (i). we get?3 (y/3)2/4 = x ? x = ?3 x y2/36? x = y2/3?3x = y2/12?312?3 x = y2On squaring both sides, we get y4 = 432x2
EXAMIANS