Probability
Definition of Probability

• Probability is a numerical measure of the Likelihood of occurrence of an event. The Value of Probability lies between 0 and 1.
• If all outcomes of an experiment are equally likely, then the Probability is given by,
  Probability of an Event = alt="" />.

Examples of Probability

• The Probability to pick a blue marble from a basket containing 10 blue marbles is 1.
• Suppose you toss a fair coin. Then the Probability of tossing a head or tail is alt="" /> 

Solved Example on Probability

A basket contains 30 apples, 20 pears and 10 peaches. What is the Probability that the First piece of fruit taken from the basket will be a peach?
Choices:
A. alt="" />
B. alt="" />
C. alt="" />
D. alt="" />
Correct Answer: C
Solution:
Step 1: Total number of fruits in the basket = 30 + 20 + 10 = 60.
Step 2: Number of peaches in the basket = 10.
Step 3: The Probability of taking a peach from the basket = alt="" />.  [From the definition.]

Related Terms for Probability

• Event
• Outcome

Additional Links for Probability

• Click here for samples
• Back to Mathematics Dictionary