Two cyclists start on a circular track from a given point but in opposite directions with speeds of 7 m/sec and 8 m/sec respectively. If the circumference of the circle is 300 metres, after what time will they meet at the starting point ?

Correct Answer: 300 sec
Time taken by the two cyclists to cover one round of the track is $$\frac{300}{7}$$ sec and $$\frac{300}{8}$$ sec respectively.
∴ Required time :
= L.C.M. of $$\frac{300}{7}$$ and $$\frac{300}{8}$$
= 300 sec