( \frac91216 ). Summary of Key Formulas Used | Concept | Formula | |---------|---------| | Classical probability | ( P(A) = \fracA ) | | Conditional probability | ( P(A|B) = \fracP(A \cap B)P(B) ) | | Multiplication rule | ( P(A \cap B) = P(A)P(B|A) ) | | Bayes' theorem | ( P(A|B) = \fracP(BP(B) ) | | Binomial probability | ( P(X=k) = \binomnk p^k (1-p)^n-k ) | | Complement rule | ( P(A) = 1 - P(\neg A) ) | These exercises illustrate the most common reasoning patterns in introductory probability. Practice with variations (more dice, different decks, multiple events) to build intuition.
Favorable pairs: (1,6), (2,5), (3,4), (4,3), (5,2), (6,1) → 6 outcomes. [ P(\textsum = 7) = \frac636 = \frac16 \approx 0.1667 ] probabilidade exercicios resolvidos
Given: [ P(D) = 0.001,\quad P(T^+|D) = 0.99,\quad P(T^+|\neg D) = 0.01 ] By Bayes' theorem: [ P(D|T^+) = \fracP(T^+D)P(D) + P(T^+ ] [ = \frac0.99 \times 0.0010.99 \times 0.001 + 0.01 \times 0.999 ] [ = \frac0.000990.00099 + 0.00999 = \frac0.000990.01098 \approx 0.09016 ] ( \frac91216 )