Question

Four friends wanted to cycle wanted to cycle independently but wanted to keep meeting each other during their rides. They formed a path which is represented by the diagram above. Each person rode round a different circle, one at the rate of six miles an hour, another at the rate of nine miles an hour, another at the rate of twelve miles an hour, and the fourth at the rate of fifteen miles an hour. They agreed to ride until all met at the center, from which they started, for the tenth time. The distance round each circle was exactly one-third of a mile. When did they finish their ride?

Answer 1

but where is the diagram friend.....

Answer 2

Exactly where is the diagram..plzz send the diagram first....