Two friends A and B live at a distance of 140 km. Both start driving towards…
2023
Two friends A and B live at a distance of 140 km. Both start driving towards each other in a straight line to meet. If A drives at 80 km/hr and B drives at 40 km/hr, then how many km apart will they be exactly 45 minutes before they meet?
Answer: B. 90 km — First, calculate the relative speed of A and B driving towards each other. Relative Speed = 80 km/hr + 40 km/hr = 120 km/hr. Next, convert the time before…
- A.
70 km
- B.
90 km
- C.
100 km
- D.
80 km
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Correct answer: B
First, calculate the relative speed of A and B driving towards each other. Relative Speed = 80 km/hr + 40 km/hr = 120 km/hr. Next, convert the time before meeting into hours: 45 minutes = 45/60 hours = 0.75 hours. Finally, calculate the distance covered by both together in this time: Distance = Relative Speed × Time = 120 km/hr × 0.75 hr = 90 km.