not sure of the question asked, although 5^3 is 125. 5^3 means that you have the equivalant of (5x5x5) (or 3 fives multiplied by themselves.) It is simple work of 5x5 is = to 25, and 25 x 5 = 125. If you are having trouble wrapping your head around the multilplication or the idea as a whole, study the individual parts seperate, then come back with an open mind.
Hope This helped!
-Rigo