Probability is the chance that something will happen; there are two kinds of probability, theoretical and experimental.
Experimental probability = numberofeventoccurences / (Total number of trials)
Theoretical probability = (Number of favourable outcomes) / (Total number of outcomes)
Example 1: Which of the following is an experiment?
Tossing a coin
Rolling a single 6 sided die
Choosing a ball from a jar
All of the above
Example 2: A number from 1 to 13 is chosen at random. What is the probability that the selected number is a prime number?
Answer: Prime numbers from 1 to 13 are 2, 3, 5, 7, 11, 13.
Number of prime numbers = 6
Probability of selecting a prime number = 6⁄13
Example 3: What is the probability of drawing a red colored ace from a set of cards ?
Total number of cards in a set = 52
Total number of red colored cards = 13 x 2 = 26
Number of ace’s in red colored cards = 2
probability of drawing an ace from a red colored card = 2⁄26 = 1⁄13