The distance between the places H and O is D units. The average speed that gets a person from H to O in a stipulated time is S units. He takes 20 minutes more time than usual if he travels at 60 km/h, and reaches 44 minutes early if he travels at 75 km/h. The sum of the numerical values of D and S is:
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e 384
The distance between two points is 'D' units and the speed is 'S' units then the time = D / S
By the first condition,
⇒ t + (1 / 3) = D / 60 (1)
By the second condition,
⇒ t - (11 / 15) = D / 75 (2)
By solving (1) & (2) we would get t = 5 & D = 320
We know that t = D / S
⇒ S = 320 / 5 = 64
⇒ D + S = 320 + 64 = 384