Every 12 minutes, Bus A completes a trip from P to X to S to X to P. Every 20 minutes. Bus B completes a
trip from Q to X to T to x to Q. Every 28 minutes,
Bus C completes a trip from R to X to U to X to R. At
1:00 p. m., Buses A, B and C depart from P. Q and R.
respectively, each driving at a constant speed, and each
turning around instantly at the endpoint of its route.
Each bus runs until 11:00 p. m. At how many times
between 5:00 p. m. and 10:00 p. m. will two or more buses
arrive at X at the same time?