Q14 of 189 Page 500

A cylinder and a cone have equal radii of their bases and equal heights. If their curved surface areas are in the ratio 8:5, show that the radius and height of each has the ratio 3:4.

Given,


Curved surface area of cylinder = curved surface area of cone = 8:5


Let C.S.A of cylinder = 8x


C.S.A of cone = 5x


As mention above cone and cylinder have equal radius and equal height







100h2 = 64h2 + 64r2


100h2 – 64h2 = 64r2


36h2 = 64r2





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