Farmer Fruitless needs to travel from the north-east corner of his square, ploughed field to the south-west corner. Each side of the field is 100 m long, and a narrow road runs along its northern edge. He is dressed for bad weather, wearing wellington boots and a coat with a waterproof pocket for his graphic display calculator.
He can walk at \(3\text{ m/s}\) along the road, but only \(2\text{ m/s}\) across the field. He uses his GDC to find the minimum possible time for his journey. What answer should he obtain?
