the total surface area of solid right circular cylinder is 231cm it's curved surface area is two third of the total surface area.find ridius and height of cylinder
Answers
Curved surface area = (2/3) x Total surface area
2 Π r h = (2/3) x 231
2 Π r h = 2 x 77
2 Π r h = 154
Total surface area of the cylinder = 231 cm²
2 Π r (h + r) = 231
2 Π r h + 2 Π r² = 231
154 + 2 Π r² = 231
2 Π r² = 231 - 154
2 Π r² = 77
2 x (22/7) x r² = 77
r² = 77 x (7/22) x (1/2)
r² = (7/2) x (7/2)
r = (7/2) cm
2 Π r h = 154
2 x (22/7) x (7/2) x h = 154
h = 154 x (1/2) x (7/22) x (2/7)
h = 7 cm
Radius = 3.5 cm
Height = 7 cm
