Enter the number of favorable outcomes and total possible outcomes to calculate the probability of an event.
How to Calculate Probability
Probability is a measure of the likelihood that an event will occur. It is expressed as a number between 0 and 1, where 0 indicates impossibility and 1 indicates certainty.
Probability Formula
The basic probability formula is:
\[P(E) = \frac{\text{Number of Favorable Outcomes}}{\text{Total Number of Possible Outcomes}}\]
Where:
\(P(E)\) is the probability of event E occurring
Number of Favorable Outcomes is the count of outcomes where E occurs
Total Number of Possible Outcomes is the count of all possible outcomes
Calculation Steps
Identify the event you want to calculate the probability for.
Count the number of ways the event can occur (favorable outcomes).
Count the total number of possible outcomes.
Divide the number of favorable outcomes by the total number of possible outcomes.
Example
Let's calculate the probability of rolling a 6 on a standard six-sided die.
Event: Rolling a 6
Favorable outcomes: 1 (only one face shows 6)
Total possible outcomes: 6 (the die has six faces)
Probability calculation:
\(P(\text{Rolling a 6}) = \frac{1}{6} \approx 0.1667\)
Therefore, the probability of rolling a 6 is 1/6 or approximately 0.1667 or 16.67%.
Visual Representation
This diagram illustrates the probability of rolling a 6 on a standard six-sided die. The green section represents the favorable outcome (rolling a 6), while the white section represents all other possible outcomes.