I bought a certain number of marbles at rate of 59 marbles for rupees 2 times M, where M is an integer. I divided these marbles into two parts of equal numbers, one part of which I sold at the rate of 29 marbles for Rs. M, and the other at a rate 30 marbles for Rs. M. I spent and received an integral number of rupees but bought the least possible number of marbles. How many did I buy?
3 friends A, B & C run on a circular track of 30 km with a speed of 5kmph, 7kmph & 8kmph respectively . They started from a point of that track A & B run clockwise whereas C runs anticlockwise at same time. So find out after how many hours they all meet again?
A. 25 hours
B. 15 hours
C. 30 hours
D. 20 hours