Compare the motion of two humpback whales. Which humpback whale was moving at a lower speed?

 - a humpback whale that moved 20miles in 10hours
 - a humpback whale that moved 25miles in 10hours
Look at the distance each humpback whale moved and the time it took to move that distance.
One humpback whale moved 20 miles in 10 hours.
The other humpback whale moved 25 miles in 10 hours.
Notice that each humpback whale spent the same amount of time moving. The humpback whale that moved 20 miles moved a shorter distance in that time. So, that humpback whale must have moved at a lower speed.