Please solve and explain this question to me .

radius of a circular track is 63 m . 2 Cyclists A and B start together at speeds 33m/min and 44m/min. After how many min will they meet again ata the starting point ?
answer : 84min

length of track = 2 X 63 X Pi= 126 Pi

time taken by A for 1 round = 126 Pi / 33 = 12 minutes

time taken by B for 1 round = 126 Pi / 44 = 9 minutes

LCM OF 9 AND 12 IS 36

Answer = 36 minutes

First caclulate the circumference of the track.

c = 2 * pi * r
c =~ 395.8m

395.8m / 33m/min = 12 min
395.8m / 44m/min = 9 min

The lowest number divisible by both 9 and 12 is 36. So they will meet every 36 minutes.

I don't know where 84min comes from, something is wrong.

2π 63 / 33 = time for 1 circuit ≈ 12 min for A

2π63 / 44 ≈ 8 min for B...thus at 48 min they will both be at the starting point for the 1st time

{after starting }