150 litres of water contains 0.3 litres of harmful substances ( i am assuming harmful as germs)
so 1 litre of water contains 0.3/150 litres of germs.
(1/2)^n * 0.3/150 < 0.09/100, where n number of grams of chlorine required.
=> (1/2)^n < 0.45
=> we need minimum of 2 gms of chlorine
so 1 litre of water contains 0.3/150 litres of germs.
(1/2)^n * 0.3/150 < 0.09/100, where n number of grams of chlorine required.
=> (1/2)^n < 0.45
=> we need minimum of 2 gms of chlorine
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