SOLUTION: if a jet was flying 2400 miles, jet stream it took 5 hours how fast is the jet going

"Per" means "divided by", so

to find miles per hour, you just divide miles by hours:

Divide 2400 miles by 5 hours like this:

   480
5)2400
  20
   40
   40
     0
     0
 
and you get 480 miles per hour.

Edwin