Probability Concept:
It is the basis of statistical quality controls. A probability generally refers to totality of possible occurrences. It is the order used to follow sampling Inspection and operation of control charts. It is numerical scale to make consistent measurements for comparing the probabilities of two or more occurrences.
Laws of probability:
If events are mutually exclusive i.e. only one event can occur at a time, and the probability of occurrence of first event is P1, of second event is P2, then the probability P of occurrence of first or second event is equal to (P1 + P2). This law is called addition law of probability.
If the events are mutually independent (and not mutually exclusive) i.e. the probability of the events occurring together or in a particular order is given by the product of the individual probabilities of the events. This law is called multiplication law of probability.
Probability of success, ‘P’ and probability of failure ‘Q’ remain constant for all the components in the sample drawn in ‘n’ trials. The probability of achieving r successes is given by the term P(R) of the Binomial Expansion of
