Question 1204956
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In the two hours that the prop plane travels before the jet plane starts, the prop plane travels 2*190 = 380 miles.<br>
Once the jet plane starts, it catches up to the prop plane at a rate equal to the difference between the speeds of the two planes, which is 570-190 = 380 mph.<br>
The number of hours it takes the jet plane to travel 380 miles more than the prop plane, at a catch-up rate of 380 mph, is 380/380 = 1.<br>
ANSWER: The jet plane overtakes the prop plane 1 hour after it starts flying.<br>