Calculate the probability of a single event.
Probability measures the likelihood of an event occurring, expressed as a number between 0 (impossible) and 1 (certain). For a single event with equally likely outcomes, P(event) = (number of favorable outcomes) / (total number of possible outcomes).
P(event) = favorable / possible. P(event') = 1 − P(event). Odds for = favorable : unfavorable. Odds against = unfavorable : favorable.
Probability is the ratio of favorable outcomes to total outcomes (fraction of success). Odds compare favorable to unfavorable outcomes. For example, if P = 1/6, odds for are 1:5 and odds against are 5:1.
Yes. Multiply the decimal probability by 100%. For example, P = 0.25 = 25%. Percentages are a common way to communicate probabilities in everyday contexts like weather forecasts ("30% chance of rain").