Question

At a train station, freight trains depart at a rate of 2 trains every 30 minutes and passenger trains depart at a rate of 1 train every 90 minutes. At this rate, how many total trains will depart from the station in a 12 hour period?

Answer 1

There would be 48 freight trains and 8 passenger trains in 12 hours, the total of trains would be 56 trains.

Answer 2

first, 2 freight trains every 30 mins is 4 trains every hour, which is 48 trains in 12 hours (12x4)
then, a passenger train every 90 minutes (1.5 hrs) is 2 trains every 3 hours, which is 8 trains in 12 hours (2x4)
therefore, 48+8= 56 trains in total
:)