A freight train from city A to city B and a passenger train from city B to city A left the cities at the same time, at 10 am, he
ading towards each other. The distance between the cities is 360 miles. The freight train is traveling at 50 mph, the passenger train is traveling at 70 mph. At what time will the trains pass each other?
Since each of the trains are going opposite ways, adding their speed is possible. One is going at 50 mph, and the other is going at 70 mph, so that adds up to 120 mph. Because we need to know when they <u>meet </u> (not finish) we have to divide 360 by two, because there are two trains. 360÷2=180. 180-120=60. And because 120/2=60, this means that it will take 1 hour and 30 minutes for the trains to meet (The 120 is the full hour, and the 60 is the half hour). Now all we need to do is add the time they both start and 1 hour & 30 minutes. 10:00 AM+1 hour and 30 mins=11:30 AM, so therefore the answer is 11:30 AM.
To answer this question I tried to find a common multiple of 21 and 35 which I found to be 105. As they are in minutes 105 is 1 hour and 45 minutes; after this I found 1 hour 45 munutes after 7:30, I then got 9:15 9:15 is my answer