A person walking at 5/6 of his usual speed reaches his focal office 12 minutes late. What is his usual time? MCQ with Answer and Explanation

Explanation:
New speed = 300 / 4 = 75 km/h. Since new speed is original speed + 15 km/h, original speed = 75 - 15 = 60 km/h.

Explanation:
Total distance = 10 + 12 = 22 km. Total time taken = 10/12 + 12/10 = 5/6 + 6/5 = (25 + 36) / 30 = 61 / 30 hours. Average speed = 22 / (61/30) = 660 / 61 = 10.82 hours (approx 10.83 km/h).

Explanation:
Speed = 72 * (5/18) = 20 m/s. Distance in 15 seconds = Speed * Time = 20 * 15 = 300 meters.