Compare the motion of three motorboats. Which motorboat was moving at the lowest speed?

 - a motorboat that moved 175miles north in 5hours
 - a motorboat that moved 40miles west in 5hours
 - a motorboat that moved 195miles north in 5hours
Look at the distance each motorboat moved and the time it took to move that distance. The direction each motorboat moved does not affect its speed.
Notice that each motorboat moved for 5 hours. The motorboat that moved 40 miles moved the shortest distance in that time. So, that motorboat must have moved at the lowest speed.