A cylindrical pipe has inner diameter of 7 cm and water flows through it at 192.5 litres per minute. Find the rate of flow in kilometres per hour.

Explanation

`d=7cm`

`r=7/2 cm`

water flow through pipe in one hour=`192.5 xx 60` litre

`= 192.5 xx 60 xx 1000 cm^3 `

`1 litre = 10^3 cm^3`

volume=`pi r^2 l`

`= 22/7 xx 7/2 xx 7/2 xx l = 192.5 xx 60 xx 1000`

`=> l = 2/ (7 xx 11) xx 192.5 xx 60 xx 1000`

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