Three persons P, Q, R run along a circular track at speeds of 3 km/h, 4 km/h, 6 km/h, respectively. If the length of the track is 36 km, then after how much time will they meet again at the starting point?
Answer & explanation
Correct answer: option 2
Time taken by P to cover the track = \(\frac{36}{3}\)
= 12 hrs
Time taken by Q to cover the track = \(\frac{36}{4}\)
= 9 hrs
Time taken by R to cover the track = \(\frac{36}{6}\)
= 6 hrs
LCM of 12, 9 and 6 = 36
Therefore, they all will meet again at the starting point after 36 hours.