Question

Let ABC be a right-angled triangle with BC as the hypotenuse. Lengths of AB and AC are 15 km and 20 krn, respectively. The minimum possible time, in minutes, required to reach the hypotenuse from A at a speed of 30 km per hour is

• A. 24
• B. 27
• C. 34
• D. 37

Answer 1

Answer: (A)

24

Answer 2

In a 3, 4, 5 triangle, the length of the altitude to the hypotenuse is calculated as $\frac{3 \times (4) }{ 5} = 2.4.$
Therefore, in a 15, 20, 25 triangle, it is 12. This represents the shortest distance from point A to side BC.
At a speed of 60 km/hr, which is equivalent to 1 km/min, it would take 24 minutes to cover a distance of 24 km.