Question

A small airplane flies 840 miles with an average speed of 280 miles per hour. 1.5 hours after the plane leaves, a Boeing 747 leaves from the same point.

Both planes arrive at the same time; what was the average speed of the 747?

Answer 1

Answer:560 miles per hour

Explanation:

840/280= 3 hours

3-1.5=1.5 hours

840/3=280

The 3 is 3 half hours so in a half hour, the 747 traveled 280 miles so in an hour it would travel 560. So the speed of the 747 was 560 mph.