Two planes leave Toronto and New York City at the same time each day going to the other city on the same path. One plane travels at 550 km/h and the other at 600 km/h. Assuming the planes are travelling at the same height, how far apart are they one hour before they meet?
To find out how far apart the planes are one hour before they meet, we need to calculate the distance each plane has traveled in that one hour.
The plane traveling at 550 km/h will have traveled a distance of 550 km/h * 1 h = <<550*1=550>>550 km.
The plane traveling at 600 km/h will have traveled a distance of 600 km/h * 1 h = <<600*1=600>>600 km.
Since the planes are traveling towards each other, the total distance between them one hour before they meet would be 550 km + 600 km = <<550+600=1150>>1150 km. Answer: \boxed{1150}.