A and B go around a circular track of length 600 m on a cycle at speeds of 36 kmph and 54 kmph. After how much time will they meet for the first time at the starting point?	Choose the correct choice:  A) 110 sec  B) 130 sec  C) 120 sec  D) 140 sec  E) 150 sec
120 sec   120 sec   Time taken to meet for the first time at the starting point   = L120 secM { length of the track / speed of A , length of the track / speed of B}   = L120 secM { 600/ (36 * 5/18) , 600/ (54 * 5 /18) }   = L120 secM (60, 40) = 120 sec.
<result>C</result>
A and B go around a circular track of length 600 m on a cycle at speeds of 36 kmph and 54 kmph. After how much time will they meet for the first time at the starting point?