Town C is located due east of Town A and due south of Town B. Noah drove for 10 hours from Town A to Town C at 7 mph, then 7 hours from Town C to Town B at the same speed. Vern flew directly from Town A to Town B at three × Noah’s speed. What was Vern’s travel time, in hours?

If Vern's travel time were 3 hours, he would be traveling at a speed of 20 mph (since he is flying at three times Noah's speed of 7 mph). This would imply a distance from Town A to Town B of only 60 miles. However, given Noah's travel times and distances, this estimation is inconsistent with the distances calculated.

A travel time of 4 hours implies Vern is flying at 15 mph. This results in a distance of 60 miles from Town A to Town B. However, based on Noah’s route and total distances calculated from his journey, this distance is still too short, as it does not match the calculated distances from Noah's trips.

If Vern traveled for 6 hours, he would be flying at 18 mph, resulting in a distance of 108 miles. This exceeds the calculated distance based on Noah's route, making this option inconsistent with the established travel distances.

A travel time of 7 hours would mean Vern is flying at 15 mph, covering 105 miles. However, this option also does not fit the computed distances based on Noah's travels, leading to the conclusion that it cannot be correct.