Four times the area of the curved surface of a cylinder is equal to 6 times the sum of the areas of its bases. If its height is 12 cm, find its curved surface area.
Let the radius and height of the cylinder be r and h respectively.
Curved surface area of cylinder =2πrh
Area of bases =πr2
Sum of areas of bases =2πr2
According to the question,
4×Curved surface area=6×Sum of areas of bases
∴r=23×12=8 cm [∵ h = 12 cm, given]
∴ Curved surface area of the cylinder =2πrh