An airliner travels 45 miles in 5 minutes What is its speed

An airliner travels 45 miles in 5 minutes. What is its speed in miles per hour?

Please set up the problem so I can see the unit cancellations.

Thank you.

Solution

distance = speed*time

Speed = distance/time

distance = 45 miles

time = 5 minutes = 5/60 = (1/12) hr

Speed = 45 miles/(1/12) hr

Speed = 45*12 = 540 miles/hr