## Batting Average

You may not think that a baseball player uses math, but they do. One way they use math is to calculate their batting average. The batting average is the average performance of a batter, expressed as a ratio of a batter's safe hits per official times at bat. The formula for a player's batting average is shown in the picture below

## Earned Runs Average

The earned run average or ERA is the mean of earned runs given up by the pitcher per every nine innings they pitch. An earned run is a run that was not affected by errors.

Example: Tim Lincecum 2012 ERA: 5.74 (17 earned runs, 26.2 total innings pitched)

## Pitch Count

The pitch count is the number of pitches a pitcher throws in one game. Coaches use this to know when to take a pitcher out of a game.

## Field Measurements

The dimensions of a baseball field are very important to know. For example the distance from the pitchers mound and home plate is exactly 60ft 6in. This is important so players know how fast they need to run from base to base or what is a fair or foul ball.

## Player Stats

The player statistics let the player know how well they are doing that season. Player stats contain even more ways baseball players use math including batting average, ERA, on base percentage, RBI (Runs Batted In), etc.

## Position Numbering

In baseball, each defensive position is given a number 1-9. For example maybe the coach will say 3 5 which means throw the ball to first then 3rd. Here is a picture showing each position and its number.