A person moves from place A for place B at 12:00 PM at a speed of 12.5 km/h, stayed at place B for 2.5 hours and returned to place A at a speed of 17.5 km/h. He came back to place A at 8:30 PM. What is the distance between places A and B (in km)?
Answer & explanation
Correct answer: option 2
Total time in journey 8:30 PM - 12:00 PM = 8.5 hours
Total effective time in journey = 8.5 hours - 2.5 hours (rest time) = 6 hours
A to B : B to A
Speed ⇒ 12.5 : 17.5
5 : 7
Time ⇒ 7 : 5 = 12 (Total)
Total Time = 12R = 6 hrs.
1R = 0.5 hr
So, A's time = 7R = 7 × 0.5 = 3.5
Distance = Speed × Time
= 12.5 km/h × 3.5 = 43.75 km