Two people leave town at the same time traveling in opposite directions. If one person travels at 50 mph and the other travels 60 mph, how long will it take them to be 550 miles apart?

Two trains leave different cities heading toward each other at different speeds ... At the same time Train B, traveling 60 mph, leaves Eastford heading toward Westford ... Since an equation remains true as long as we perform the same operation ... that the train's rate is 40 mph, which means it will travel 40 miles in one hour.