The probability model of an event is defined as a number between one and zero. In reality however there is practically nothing that has a probability of 1 or 0. The theoretical probability of an event E is the fraction of times we expect E to occur if we show again the same experiment over and over. The expected probability approaches the theoretical probability as the number of trials gets bigger and bigger. Thus, If E consists of a single outcome s, we refer to P (E) as the probability of the outcome s, and write P(s) for P (E).
Examples on Probability Model
Following are some examples on Probability Model.
Example 1:
A jar contains 5 white, 6 black, 4 green and 8 yellow marbles. If a particular marble is selected at random from the jar, what is the probability of choose a white marble? a green marble? a black marble? a yellow marble?
Solution:
Probability = number of way to choose white/total number of the marble = 5/23
Probabilty = number of way to choose green/total number of the marble = 4/23
Probability =number of way to choose black/total number of the marble = 6/23
Probability =number of way to choose yellow/total number of the marble = 8/23
A bag contains 6 orange, 4 red, 7 blue and 5 yellow balls. If a single ball is selected at random from the bag, what is the probability of choose a orange ball? a red ball? a blue ball? a yellow ball?
Solution:
Probability (orange) =number of way to choose orange/total number of the ball = 6/23
Probability (red) =number of way to choose red/total number of the ball = 4/23
Probability (blue) =number of way to choose blue/total number of the ball = 7/23
Probability (yellow) =number of way to choose yellow/total number of the ball = 8/23