Free Probability Calculator
Calculate the probability of an event as the ratio of favorable outcomes to total possible outcomes.
Probability
0.300000
Probability (%)30.0000
Odds in Favor0.4286
Probability vs Favorable Outcomes
How to Calculate Probability
Formula
P(A) = Favorable outcomes / Total outcomes
Probability measures how likely an event is to occur, ranging from 0 (impossible) to 1 (certain). Multiply by 100 to express as a percentage. The odds in favor are the ratio of favorable to unfavorable outcomes.
Example Calculation
A bag has 3 red balls out of 10 total. What is the probability of drawing a red ball?
- 01Favorable outcomes = 3 (red balls)
- 02Total outcomes = 10 (all balls)
- 03P(red) = 3 / 10 = 0.3
- 04As a percentage: 0.3 * 100 = 30%
- 05Odds in favor: 3 / (10 - 3) = 3/7 ≈ 0.4286
Frequently Asked Questions
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