PROB(x_range, prob_range, lower_limit, upper_limit)

The PROB function calculates the probability that numbers in a range are between two limits.

x_range is a range of numbers with which there is associated a range of corresponding probabilities in prob_range.

lower_limit and upper_limit are the limits of the range of numbers for which we want to know the probability. If upper_limit is omitted then it becomes equal to lower_limit, and PROB calculates the probability of just the one number.

Note that the values in prob_range must total 1, and that this range and x_range must contain the same number of values.

For example, if {2, 4, 6, 8, 10} is a list of all possible outcomes of an experiment, with corresponding probabilities {0.3, 0.1, 0.1, 0.2, 0.3}, then the probability of an event being between 4 and 8 inclusive is given by the formula:

PROB({2,4,6,8,10}, {0.3, 0.1, 0.1, 0.2, 0.3}, 4, 8)

which returns 0.4.

See also:

Other statistical functions