Two trains stop on track. A and B at 8am. One stops on track A every 9 minutes and another on B every 12 minutes. At what time will the trains stop on both tracks at the same time again?? All i need is a answer please!!!
Thank you for your time -w-

Among the most famous of all meteor showers are the perseids, which occur each year in early august. in some areas the frequency of visible perseids can be as high as 40 per hour. given that such sightings are poisson events, calculate the probability that an observer who has just seen a meteor will have to wait at least five minutes before seeing another.