Question

A container contains 40 litres of milk. From this container 4 litres of milk was taken out and replaced by water. This process was repeated further two times. How much milk is now contained by the container?

• A. $26.34$ litres
• B. $27.36$ litres
• C. $28$ litres
• D. $29.16$ litres

Answer 1

The correct option is D $29.16$ litres

Amount of milk left after 3 operations $=[4\times {(1-\frac{4}{40})}^3]liters$

$\Rightarrow [40\times \frac{9}{10}\times \frac{9}{10}\times \frac{9}{10}]=29.16liters$