I really like baseball. When you look at the fielding percentage, on-base percentage, ERA, and batting average. Those things are all statistics, fractions and decimals. You get the fielding percentage by dividing the amounts of times you field the ball correctly by the amounts of times you tried to field the ball. An example is jack Wilson tried to field the ball 10 times and he made 1 error, so his fielding percentage would be 900. The on-base percentage is calculated the same way except you divide the amounts of plate appearances by how many times you got on base.

For example, Joe Randa has 20 plate appearances and he got on base 17 times, so Joe Randa would have an .850 on-base percentage. You calculate the batting average the same way as the last two examples except you divide the amounts of hits by the amounts of at bats (Walks or HBP do not count as at bats.). ERA is calculated in a different way you calculate the average amount of runs let down per inning and the you add that amount of runs for every inning until you get to nine innings. and than that number is that pitcher's ERA. For example, Paul Maholm let down 1 run per inning, so his ERA would be 9.00. This concludes my explanation on how math is used in baseball.