The diameters of two cones are equal. If their slant heights be in the ratio of 5 : 7, then find the ratio of their curved surface areas.?
Correct Answer: 5 : 7
Explanation:
Given, l1/l2 = 5/7
Now, curved surface area of the first cone = π rl1
and curved surface area of second cone = πrl2
∴ Ratio = πrl1/πrl2 = l1/l2 = 5 : 7
