People run around a circular track and meet every now and then. Throw in a song, and one can almost see Karan Johar

1. Races

2. Races
A and B stand at distinct points of a circular race track of length
120m. They run at speeds of a m/s and b m/s respectively. They
meet for the first time 16 seconds after they start the race and for
the second time 40 seconds from the time they start the race. Now,
if B had started in the opposite direction to the one he had originally
started, they would have meet for the first time after 40 seconds. If B
is quicker than A, find B’s speed.
(a) 3 m/s (b) 4 m/s
(c) 5 m/s (d) 8 m/s

3. Races
This is practically just a logical reasoning question.
They meet for the first time 16 seconds after they start the race and
for the second time 40 seconds from the time they start the race.
A and B stand at distinct points of a circular race track of length
120m. They run at speeds of a m/s and b m/s respectively. They
meet for the first time 16 seconds after they start the race and for
the second time 40 seconds from the time they start the race. Now,
if B had started in the opposite direction to the one he had originally
started, they would have meet for the first time after 40 seconds. If B
is quicker than A, find B’s speed.

4. Races
Now, we do not know their relative positions when they start the
race. But we know that the time between the first and second
meeting is 24 seconds. This is the time when they cover a relative
distance of one lap length.
Lap length
Relative Speed
= 24; Or relative speed = 5 m/s.
The question says – Now, if B had started in the opposite direction to
the one he had originally started, they would have met for the first
time after 40 seconds.

5. Races
Now, B would have crossed each other after 40 seconds if B had
reversed direction. This is higher than the 24 seconds it takes them
to cover the relative distance of a lap in the first instance.
Or, in the first instance they were
travelling towards each other.
Or, a + b = 5 m/s.
They meet for the first time 16 seconds
after they start the race.
A
B
Lap length = 120m

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