A bucket is in the form of a frustum of a cone. Its depts. Is 15 cm and the diameters of the top and the bottom are 56 cm and 42 cm respectively. Find how many litres of water the bucket can hold. [Take π = 22/7.]
Given: Depth of the bucket = height of frustum = h = 15 cm
Diameter of top of bucket = 56 cm
Diameter of bottom of bucket = 42 cm
∴ Radius of top = R = 56/2 = 28 cm
∴ Radius of bottom = r = 42/2 = 21 cm
Volume of water bucket can hold = volume of bucket which is in form of frustum
= (22/7) × 5 × (784 + 441 + 588) cm3
= (22/7) × 5 × 1813 cm3
= 22 × 5 × 259 cm3
= 28490 cm3
Now 1 litre = 1000 cm3
∴ 28490 cm3 = 28490/1000 litres
= 28.49 litres
∴ bucket can hold 28.49 litres of water
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