Question

If the radii of the circular ends of a frustum which is 45cm high are 28cm and 7cm, find the
volume of the frustum
​

Answer 1

Step-by-step explanation:

Let 'ℓ' & R be the radii of the bottom and top circular ends of a frustum of a cone, respectively and 'h' be height of cone.

Volume of the frustum of the cone =31×722×45(282+72+28×7)cm3

=722×15(784+49+196)cm3

=722×15×1029cm3=22×15×147cm3

=330×147cm3

Now, l=h2+(R−r2)=(45)2+(28−7)2=2025+441=2466

=2466=49.65cm

curved surface area of the frustum of the cone

=π(R+r)ℓ=[722∗(28+7)∗