A fox runs at a rate of 42 mi/hr and a cat runs at a rate of 44 ft/s. What is the difference in their speeds

1 mi = 5280 ft.Please show all work
Also I don't understand how you get 61.6 from 42mi/hr*5280ft/min*1hr/3600s.
Please elaborate.

The fox is faster than the cat. The difference in speed can be expressed in miles per hour OR feet per second.
http://www.flickr.com/photos/dwread/8101…

So first you need them to be at traveling in the same units so lets convert the cat's speed into miles per hour. To do this, you need to cancel out the seconds first.

44 ft -- 3600 sec
------ x ---------
1 sec 1 hr

=158400 ft per hour


158400 ft 1 mile (Next you cancel out the feet)
------------ x ------------
1 hour --- 5280 ft

=30 miles per hour


So the fox runs 42 mi/hr and the cat runs 30mi/hr

Therefore the cat runs 12 mi/hr slower.

(42mi/hr)(5280ft/mi)(hr/3600 sec) = 61.6 ft/sec
61.6 - 44 = 17.6 ft/sec difference

42 miles/hour = 42*5280 ft / 60*60 seconds = 308/5 ft/sec = 61.6 ft/sec
Remember 1 hour = 60 minutes = 60*60 seconds