PROBABILITY

PROBABILITY

1. TYPES

   • EMPIRICAL PROBABILITY
     • When probability is based on an actual experiment suppose event E is happen, when experiment is performed, then P(E) = No. of times event E occurred/ No. of times the experiment was performed
   • MEASUREMENT PROBABILITY
     • When repetition of an experiment can be avoided for exact probability. Therefore, Probability= No. of favourable outcomes/ No. of all possible outcomes
   • CLASSICAL PROBABILITY
     • Probability of an event denotes likelihood of its happening, P(E)= No. of event favourable/ No. of all possible outcomes

2. RANDOM EXPERIMENT

   • Random experiment may result in two or more outcomes. e.g. (i) tossing a coin (ii) throwing a dice

3. SAMPLE SPACE

   • Set of all possible outcomes of an experiment

4. EVENT

   • An outcome of a random experiment or an event is something that happen

5. EQUALLY-LIKELY EVENTS

   • The different outcomes have the same as equal chance of occurrence.

6. Probability of any event can never be less than 0 and not more than 1

7. SUM

   • Sum of the probability of all events is always one. e.g. Suppose these are 'n' events corresponding to a random experiment, them P(E1)+ P(E2)+ P(E3)+----P(En)= 1

8. COMPLEMENTARY EVENT

   • P(E)+ P(not E)= 1 or P(not E)= 1 -P(E) here, P(not E)=P(E) Complementary events

9. CERTAIN EVENT OR SURE EVENT

   • Probability of an event is equal to 1

10. IMPOSSIBLE EVENT

    • Probability of an event is equal to 0