Three ferry services A, B, and C leave from the same jetty at different intervals. Services A, B, and C leave the jetty once every 10 minutes, 12 minutes and 15 minutes
respectively. Given that the first ferry of the three services left the jetty together at
09 00 on a particular day, find

(a) the earliest time that the 3 ferry services next leave the jetty together again.

(b) the earliest time Amy will leave the jetty given that Amy reached the jetty on
this particular day at 09 30 and takes the ferry service B from the jetty.

(c) the time of the last ferry of Service A to leave the jetty on this particular day,
given that the jetty closes at 23 25.​