From a cask of milk containing 45 litres, 9 litres are drawn out and the cask is filled up with water.If the same process is repeated a second, then a third time, what will be the number of litres of milk left in the cask? a) 31.2 b) 20.9 c) 23.04 d) 12.39 e) 15.36

1 Answer

Answer :

C

where x is the initial quantity of milk in the cask y is the quantity of milk withdrawn in each process and n is the

number of processes.

Initial quantity:45

Withdrawn quantity=9

number of times repeated=3

Hence from the above rule it can be say that,

Formula,=[a(1-b/a)n

]

Quantity of milk left after the 3rd operation =45*(45-9)/45)^3

= 23.04 litres.

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