Two bikers are riding a circular path, the first rider completes a round in 12mins the second rider complets 18mins if they both started at the same place and time and go in same direction after how many minutes will they meet again at the starting point.
They will meet at the starting point each time the number of minutes
that have lapsed is divisible by both 12 and 18.
The smallest number of minutess which is divisible by both
12 and 18 is 36.
So they will meet at the starting point every 36 minutes.
The first time will be when 36 minutes have lapsed.
Edwin