Question

Timothy went to a baseball game. after the game, he wanted to ride the bus home. the red line and the blue line buses both stop at the stadium.
●A red line and a blue line bus both left the stadium at 4:00 p.m.
●Red line buses were scheduled to leave the stadium every 6mins
●Blue line buses were scheduled to leave If the busses run on schedule when is the next time a red line and a blue line bus will leave together?​