Question

the slant height of frustum of a cone is 4 cm and the perimeter of its circular ends are 18 cm and 6 cm find the curved surface area of frustum ​

Answer 1

Here, l = 4 cm

2πr1 = 18 cm

2πr2 = 6 cm

πr1 = 9, πr2 = 3

Curved surface area of frustum = π(r1 + r2) × l

= (πr1 + πr2) × l

= (9 + 3) × 4

= 48 cm2

Hope it helps u..

Answer 2

Answer:

the slant height of a cone=4cm

radius of a cone=6cm

curved Surface area of a cone=πrl

22÷7×6×4

=22÷7×24

528÷7

=75.42cm^2