Question

If the volume of a cylinder of height 7 cm is 448 cm cube find its lateral surface area and total surface area

Answer 1

Volume of a cylinder = π (r)^2 h               448 = 22/7 × (r)^2 × 7               448 / 22 = (r)^2               20.36 = (r)^2               4.51 = r    so, r = 4.51 cm  Lateral surface area = 2 π r h                               = 2 × 22/7 × 4.51 × 7                          = 198.44 cm^2 (approx)  Total surface area = 2 π r ( h + r )                  = 2 × 22/7 × 4.51 ×( 4.51 + 7 )               = 2 × 22/7 × 4.51 × 11.5             = 326.29 cm^2 (approx)