Q10 of 63 Page 21

The radius and slant height of a cone are in the ratio of 4 : 7. If its curved surface area is 792 cm2, find its radius. (Use π=22/7)

We have,


Let radius of cone = r =4x,


Let slant height = l =7x


Area of curved surface = πrl = 792 cm2


Now, πrl = 792


=


∴r =4×3= 12 cm


l = 7×3 = 21 cm


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