- Home
- AU Maths Methods
- Probability
Addition rule for "OR"
- Intro Lesson1:28
- Lesson: 1a11:36
- Lesson: 1b10:55
- Lesson: 1c6:01
- Lesson: 2a7:32
- Lesson: 2b8:42
- Lesson: 3a5:31
- Lesson: 3b5:30
- Lesson: 3c3:49
- Lesson: 3d3:37
- Lesson: 4a2:54
- Lesson: 4b3:36
- Lesson: 4c2:27
Addition rule for "OR"
Lessons
⋅ P(A or B): probability of event A occurring or event B occurring during a single trial.
⋅ If events A, B are mutually exclusive:
- events A, B have no common outcomes.
- in the Venn Diagram, the circle for A and the circle for B have no area of overlap.
- P(A or B) = P(A) + P(B)
⋅ If events A, B are not mutually exclusive:
- events A, B have common outcomes.
- in the Venn Diagram, the circle for A and the circle for B have an area of overlap representing the event "A and B".
- P(A or B) = P(A) + P(B) – P(A and B)
⋅ If events A, B are mutually exclusive:
- events A, B have no common outcomes.
- in the Venn Diagram, the circle for A and the circle for B have no area of overlap.
- P(A or B) = P(A) + P(B)
⋅ If events A, B are not mutually exclusive:
- events A, B have common outcomes.
- in the Venn Diagram, the circle for A and the circle for B have an area of overlap representing the event "A and B".
- P(A or B) = P(A) + P(B) – P(A and B)
- Introduction
- 1.Mutually Exclusive VS. Not Mutually Exclusive
Consider the experiment of rolling a die.a)Event A: an even number is thrown
Event B: an odd number is thrown
i) List the outcomes for:
⋅ event A
⋅ event B
⋅ event A or B
⋅ event A and B
ii) Mark the outcomes on the Venn Diagram. Are events A, B mutually exclusive?
iii) Determine the following probabilities:
⋅ P(A)
⋅ P(B)
⋅ P(A or B)
⋅ P(A and B)
b)Event A: an even number is thrown
Event B: a multiple of three is thrown
i) List the outcomes for:
⋅ event A
⋅ event B
⋅ event A or B
⋅ event A and B
ii) Mark the outcomes on the Venn Diagram. Are events A, B mutually exclusive?
iii) Determine the following probabilities:
⋅ P(A)
⋅ P(B)
⋅ P(A or B)
⋅ P(A and B)c)Supplementary info on mutually exclusive and addition rule. - 2.There are 20 students in a class. 9 students like pizza and 7 students like pasta. Of these students, 3 students like both. Determine the probability that a randomly selected student in the class like pizza or pastaa)using the formula.b)using the Venn Diagram.
- 3.A card is drawn from a standard deck of 52 cards. Determine the probability that:a)a heart or a spade is drawn.b)a heart or a face card is drawn.c)an ace or a face card is drawn.d)an ace or a spade is drawn.
- 4.Use the following information to determine whether the events A, B are mutually exclusive.a)P(A)=0.5 P(B)=0.3 P(AorB)=0.7b)P(A)=32 P(B)=51 P(AorB)=1513c)P(A)=127 P(B)=135 P(AandB)=0