Question 277678
Two trains are traveling towards each other on separate, parallel tracks.  Each train is traveling at a constant rate of 60 miles per hour and each train is 1/6 of a mile long.  How much time will elapse between the moment when the engines pass each other and the cabooses pass each other?

Since the trains are travelling in opposite direction their effective speed will be 120 miles per hour.

they are 1/6 mile long

both trains are 2/6 miles long.

If the have to completely cross eache other they have to be 2/6 miles away.

distance = 2/6

speed = 120 mph

time = distance/rate

2/6 /  120

2/ 6*120

2/720 =0.00278 hours

0.00278 * 3600  1hour = 3600  seconds

= 10 seconds