Example 1: Fill in the given values to find the volume: V = (π·r^{2}·H) ÷ 3 V = (π·8^{2}·12) ÷ 3 V = 804.2 cm^{3} rounded to 1 d.p. For simplicity, we'll assume that all measurements are in centimetres Example 2: The volume is 1200 cm^{3}. Find the radius by solving backwards. V = (π·r^{2}·H) ÷ 3 1200 = (π·r^{2}·15) ÷ 3 3600 = π·r^{2}·15 76.39 = r^{2} dividing 3600 by π and by 15 8.7 = r rounded to 1 d.p. Example 3: Find r first. Then find the volume. r^{2} + 13^{2} = 25^{2} r^{2} = 625 - 169 r^{2} = 456 r = 21.35 Now find the volume: V = (π·r^{2}·H) ÷ 3 V = (π·(21.35)^{2}·13) ÷ 3 V = 6205.4 cm^{3} Example 4: The volume is 2200 cm^{3}. The diameter is 32 cm. Find the height. V = (π·r^{2}·H) ÷ 3 2200 = (π·16^{2}·H) ÷ 3 using radius 16 6600 = π·16^{2}·H 8.2 cm = H dividing both sides by π·16^{2} |