Say h = height of the frame of lampshade, looks like cylindrical shape r = radius Total height is h = (2.5+30+2.5) cm = 35cm and r = (20/2) cm = 10cm Use curved surface area formula to find the cloth required for covering the lampshade which is 2πrh = (2×(22/7)×10×35) cm2 = 2200 cm2 Hence, 2200 cm2 cloth is required for covering the lampshade.