A conical pit of top diameter 3.5 m is 12 m deep. What is its capacity in kilolitres?

Solution:

Volume of a cone having radius 'r', and height 'h' = 1/3πr²h

Diameter of the conical pit, 'd' = 3.5 m

Radius of the conical pit, 'r' = 3.5/2 m = 1.75 m

Depth of the conical pit, 'h' = 12m

Volume of conical pit = 1/3πr²h

= 1/3 × 22/7 × 1.75 m × 1.75 m × 12 m

= 38.5 m³

= 38.5 × 1 kilolitres  (1m³ = 1000 Litres = 1 kilolitres)

= 38.5 kl

Capacity of the conical pit is 38.5 kilolitres.

☛ Check: NCERT Solutions for Class 9 Maths Chapter 13

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Video Solution:

A conical pit of top diameter 3.5 m is 12 m deep. What is its capacity in kilolitres?

NCERT Solutions for Class 9 Maths Chapter 13 Exercise 13.7 Question 5

Summary:

It is given that the conical pit of top diameter 3.5 m is 12 m deep. We have found that the capacity of the conical pit is 38.5 kilolitres.

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