Subject: General Aptitude · Chapter: Time and Distance · Exam: 2007 · Marks: · Difficulty:
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?
(a)20 sec
(b)100 sec
(c)200 sec
(d)300 sec
Answer
Answer (as printed): D
Explanation
Time taken by the two cyclists to cover one round of the track is $\frac{300}{7}$ sec and $\frac{300}{8}$ sec respectively. $$\therefore \text{Required time} = \text{L.C.M. of } \frac{300}{7} \text{ and } \frac{300}{8} = 300\text{ sec}.$$
Explanation as extracted from the printed page; notation may be imperfect.