Math
posted by Taylor .
two trains are traveling toward each other adjacent tracks. one of the trains 230 feet long and is moving at a speed of 60 miles per hour. The other train is 220 feet long and is traveling at the rate of 70 miles per hour. Find the time interval between the moment the trains first meet until they completely pass each other

One way to look at it is to consider one of the trains to be standing still, and the second moving at (60+70) mph or 130 mph.
So from the point when the moving train meets the front of the stationary train to when its end reaches the end of the stationary train is 230+220 ft or 450 ft.
450 ft = 450/5280 miles = .085227.. miles
time = .085227../130
= .000655594 hours
= .03933 minutes
= 2.36 seconds