Water in a canal, 5.4 m wide and 1.8 m deep, is flowing with a speed of 25 km/hour. How much area can it irrigate in 40 minutes, if 10 cm of standing water is required for irrigation?

Width of canal = 5.4 m
Depth of canal = 1.8 m
In 60 min., 25 km of water flows through it.
So, in 40 min., there will be (25/60) × 40 = 50/3 km. will be available for irrigation.
Hence, the volume of water in the canal = volume of land irrigated.
Volume of canal = l × b × h = 5.4 × 1.8 × (50000/3) m³
Area of land irrigated if 10 cm standing water is required = (5.4 × 1.8 × 50000/3) × (1/0.1) m² = 1620000 m²