A bucket of height 8 cm and made up of copper sheet is in the form of frustum of right circular cone with radii of its lower and upper ends as 3 cm and 9 cm respectively. Calculate

i)  the height of the cone of which the bucket is a part

ii)  the volume of water which can be filled in the bucket

iii) the area of copper sheet required to make the bucket (Leave the answer in terms of π (Ans: 129 π cm²)

Ans: Let total height be h

=>     h/h + 8 = 3/9 (similar Δ's )

=> h = 4 cm

∴ ht. of cone which bucket is a part = 4 cm

Substitute to get Ans.: for ii) iii)