To find the probability of an event we divide the No. of favorable outcomes of an event by Total no. of outcomes.
Or
Probability P(E) = No. of favorable outcomes of an event ÷ Total no. of Outcomes
Let's take an example for better understanding:
Q- Suppose we throw a die once. What is the probability of getting a number greater than 4?
Solve:
No. greater than 4 (favorable outcomes) = 2 (5,6)
Total no. (total outcomes) = 6 (1,2,3,4,5,6)
Probability P(E) = Favorable outcomes of an event ÷ Total Outcomes
P(E) = 2÷6
P(E) = 1/3