A train is going at 14 of its usual speed and it takes an extra 60 min to ​ reach its destination. Find its usual time to cover the same distance.

Explanation

Given: A train is going at 14 of its usual speed and it takes an extra 60 min to reach its ​ destination. Concept used: 60 minutes = 1 hour Time × Speed = Distance Calculation: Let the usual speed of the train and distance be 4S km/h and D km. 1 of its usual speed = 4S/4 = S km/h 4 ​ Time to cover the distance = D/4S hours According to the question, D/S - D/4S = 1 ⇒ (4 - 1)/4S = 1/D ⇒ 3/4S = 1/D ⇒ D/S = 4/3 ⇒ D/4S = 4/(4 × 3) (Divided each side by 4) ⇒ D/4S = 1/3 So, 1/3 hours = 1/3 × 60 ⇒ 20 minutes ∴ I ts usual time to cover the same distance is 20 minutes.