A container contains 100 liters of milk. From this container, 10 liters of milk is taken out and replaced by water. This process is repeated two more times. The amount of milk left in the container now is:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 72.9 liters
Total volume of container = 100 liters
Milk taken out each time = 10 liters
Fraction of milk left after each operation = $\frac{100-10}{100}=\frac{90}{100}=\frac{9}{10}$
After 3 repetitions, amount of milk left = $100\left(\frac{9}{10}\right)^3$
$=100\cdot\frac{729}{1000}$
$=72.9$ liters
Milk left = 72.9 liters