How far is it in miles from Roy's house to the airport?

Question

Roy left home and drove straight to the airport at an average speed of 45 mph. He returned home along the same route, but traffic slowed him down and he only averaged 30 mph on the return trip. If his total travel time was 2 hours and 30 minutes, how far is it in miles from Roy's house to the airport?

Answer 1

d = rt, so t = d/r

 

d/45 + d/30 = 2.5

 

Once we find a common denominator, we don't need it anymore.

 

2d + 3d = 225

5d = 225

d = 45 miles

 

Boom.