Lets say you have a $500 bank roll betting 1% units. $5 bets, and you are winning at this "good" percentage of 55% with a average price of $1.91

55 wins = net profit $250.25
45 loss = total loss $225.00
+$25.25

with 100 bets you would win 5% of your bank roll.
This is a good return?
or do you use a higher unit price say 2% increasing your return to 10% with half the number of bets.

Where do you find the $1.91 price aswel, point starts?

This is basic i know, im learning to crawl