To the other guy btw  the math is all the  same  no matter how u  slice it  .2  =5.  i wasnt using algebra, i was  using  division.  / means  divide in math  terms. no point  of using  aleg for that. no one is wrong we looked at the math problem  from  different angle/
0.2 is not equal to 5, in the same sense that two dimes is not five dollars. Nor is 0.2 equal to five percent; it is equal to one-fifth, which is 20%. Well, theoretically, in a base 40 mathematic system, it could be accurate to say that 4 is 5% of 20, but only because that 20 would be 80, and even then I'm not sure how the concept of percent translates to other bases. 
I think to sum it up, he wasn't questioning your division skills, just that you were diving in the wrong direction or just completely misunderstanding the concept of percentage.