A village having a population of 4000 requires 150 litres of water per head per day. It has a tank measuring 20m × 15m × 6m. The water of this tank will last for

Correct Option (B)

To determine the duration for which the water in the tank will last, the total volume of water available in the tank must be divided by the total daily water consumption of the village.

• First, calculate the volume of the tank:

Volume = Length × Width × Height

Volume = 20m × 15m × 6m = 1800 m³

• Convert the tank's volume from cubic meters to litres, knowing that 1 m³ = 1000 litres:

Volume in litres = 1800 m³ × 1000 litres/m³ = 1,800,000 litres

• Next, calculate the total daily water requirement for the village:

Daily requirement = Population × Water per head per day

Daily requirement = 4000 × 150 litres/day = 600,000 litres/day

• Finally, calculate the number of days the water will last:

Days = Total water in tank / Daily water requirement

Days = $\frac{1,800,000\text{ litres}}{600,000\text{ litres/day}}=3\text{ days}$

Thus, the water in the tank will last for 3 days.

Incorrect Options:

Options A (2 days), C (4 days), and D (5 days) are incorrect because the calculations based on the provided tank dimensions, village population, and per capita water requirement yield a duration of exactly 3 days. Any other duration would contradict the derived result.