A, B and C run around a circular track starting from the same point simultaneously and in the same direction at speeds of 4 kmph, 6 kmph and 8 kmph respectively. If the length of the track is 400 meters, when will A, B and C meet at the starting point for the first time after they started the race?
Choose the correct choice from the following
A) 1 minute	B) 5 minutes	C) 12 minutes	D) 20 minutes	E) 24 minutes

Rationale: 4 kmph , 6 kmph and 8 kmph is equal to 4000 / 60 mtrs / min , 6000 / 60 mtrs / min and 8000 / 60 mtrs / min or 200 / 3 , 100 , 400 / 3 mtrs / min respectively . seeing this we can infer that the answer should be at least divisible by 3 . ( minutes in options are integers . so if the answer is not divisible by 3 , we will have 200 / 3 * answer = distance traveled by a in fractions whereas 100 * answer = distance traveled by a as integer ) so , a , b and d are out . at 12 min a , b and c will travel 800 , 1200 and 1600 mtrs respectively . length of the circle is given as 400 mtrs . as 800 , 1200 and 1600 are divisible by 400 , we can say that a , b and c will be at starting point after 12 min . hence , c will be the answer .
Answer: C