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Statistics Resources

This guide contains all of the ASC's statistics resources. If you do not see a topic, suggest it through the suggestion box on the Statistics home page.

What is Probability?

Probability is simply a way of measuring how likely some event is to happen. Common ways of reporting probability are: 

  • fractions
  • decimals
  • percentages

Converting between these different values uses simple mathematical functions:

  • fraction to decimal -> divide the values in the fraction (ex: 1/2 = .5)
  • decimal to percentage -> multiple by 100 (ex: .5 * 100 = 50%)

This guide will introduce you to common probability concepts from simple probability to complex probabilities involving multiple events. Whenever you're thinking about how to get started, use this basic probability "formula" as a guide:

number of successful/desired outcomes
------------------------------------------------------------
total number of possible outcomes