Useful formulas

Question 1

Probability Range

Answer 1

0 <= P(A) <= 1

Question 2

Rule of Complementary Events

Answer 2

P(A’) + P(A) = 1

Question 3

Addition Rule

Answer 3

P(A or B) = P(A) + P(B) - P(A and B)

Question 4

Mutually Exclusive Events

Answer 4

P(A and B) = 0

Question 5

Independent Events

Answer 5

P(A | B) = P(A) or P(B | A) = P(B)

Question 6

Conditional Probability

Answer 6

P(A | B) = P(A and B) / P(B) or P(B | A) = P(B and A) / P(A)

Question 7

Multiplication Rule

Answer 7

P(A and B) = P(A | B) x P(B) or P(B and A) = P(B | A) x P(A)

Question 8

P(AB) != P(BA)

Answer 8

P(AB) = P(A)xP(B) (πρώτα έγινε το Α γεγονός και μετά το Β) -> compound probability (σύνθετη πιθανότητα)

Question 9

P(A and B) = P(B and A)

Answer 9

Τα 2 γεγονότα έγιναν ταυτόχρονα