Answer:
30 hours
Step-by-step explanation:
Average speed = distance/time
Let the time taken for each plane to pass each other be t
Average speed of plane that left from New York = 650 mph
Distance covered = 650t miles
Average speed of plane that left from Mexico = 550 mph
Distance covered = 550t miles
Distance apart = 3000 miles
650t - 550t = 3000
100t = 3000
t = 3000/100 = 30 hours