Question

an open metal bucket is in the shape of a frustum of a cone of height 16 cm with radii of its lower and upper ends as 8cm and 20 cm respectively find the cost of milk which can completely filled rupees 20 per litre

Answer 1

height of the bucket = 16 cm
Radius of the lower(r) = 8 cm
Radius of the upper (R) = 20 cm
Volume of the bucket = ⅓πh(r² + R² + Rr)
=⅓ × 22/7×16[(8)² + (20)² + (20×8)]
= 352/21[64+400+160]
= 352/21×624
= 10459.4286cm³
The cost of milk filled in litre = 10459.4286/1000×20
= 209.188572 Rs
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