Calculate earned run average


To calculate earned run average (ERA) of a baseball player, just use the following formula:


Earned run average = (Number of earned runs × 9)/(number of innings pitched)


The formula above applies only to pitchers and it is used to determine how good a pitcher is.

The formula is used to find out how many runs a pitcher allows in a baseball game.

The lower this average, the better the pitcher is at not allowing runs in the game

Pitchers usually practice a lot to keep this number as low as possible.

When computing this average, we usually round answers to two decimal places


Example #1:


A baseball player had the following performance:

Allowed 4 runs

15 innings pitched


Earned run average = (Number of earned runs × 9)/(number of innings pitched)


Earned run average = (4 × 9)/(15)


Earned run average = (36)/(15)


Earned run average = 2.4


After rounding the answer to two decimal places, we get earned run average = 2.40


Example #2:


A baseball player had the following performance:

Allowed 7 runs

34 innings pitched


Earned run average = (Number of earned runs × 9)/(number of innings pitched)


Earned run average = (7 × 9)/(34)


Earned run average = (63)/(34)


Earned run average = 1.852941


After rounding the answer to two decimal places, we get earned run average = 1.85


Example #3:


A baseball player had the following performance:

Allowed 5 runs

32 innings pitched


Earned run average = (Number of earned runs × 9)/(number of innings pitched)


Earned run average = (5 × 9)/(32)


Earned run average = (45)/(32)


Earned run average = 1.40625


After rounding the answer to two decimal places, we get earned run average = 1.41

If you are a baseball coach, you may want to choose the player in example #3 because his average is lower.

However, no one so far was able to get an earned run average of 1.41. The ERA by the player in example #2 is close to what top players of all time were able to meet







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