At the outset, each of the five friends Ade, Ben, Cal, Dan and Ethan had a positive integer number of marbles.

If Ade gave one-half of his marbles to Ben, and Ben gave a one third of what he then held to Cal, and Cal gave a quarter of what he then held to Dan, and Dan gave one fifth of what he then held to Ethan who then passes on a sixth of his holding to Ade - they would all have an equal number of marbles.

What is the minimum number of marbles that each of the five friends had at the beginning?