Question

A container has $60$ litres of milk. From this container $6$ litres of milk was taken out and replaced by water.The process was further repeated twice. The volume of milk in the container after that is _________

• A. $38.52l$
• B. $43.74l$
• C. $42.68l$
• D. $39.85l$
• E. $Noneofthese$

Answer 1

The correct option is B $43.74l$

We have,

Total quantity of milk$=60$ litre

Taken out of milk$=6$ litre(two times)

Final quantity$=?$

Solution: We know that,

Final quantity$=$Total quantity${(1-\frac{takenout}{Totalquantity})}^n$

$=60{(1-\frac{6}{60})}^3$

$=60{(1-\frac{1}{10})}^3$

$=60\times \frac{9}{10}\times \frac{9}{10}\times \frac{9}{10}$

Thus, final quantity of milk$=43.74$ litre

Hence, this is the answer.