ANSWERS
1. The probability of any event is between one and o. What is the equation
for this?: For any event A, 0 P(A) d 1.d
2. The sum of all possible probabilities is___?: One, the equation is :P(S) = 1
3. What is the complement rule? or the probability that an event does not occur
is 1 minus the probability that it does occur.: P(not A) = 1 - P(A)
4. In probability, "OR" means either one or the other or both.: P(A or B) =
P(event A occurs or event B occurs or both occur)
5. Two events that cannot occur at the same time are called: disjoint or
mutually exclusive
6. The Addition Rule for Disjoint Events:: If A and B are disjoint events, then
P(A or B) = P(A) + P(B).
7. P(A and B) =: P(event A occurs and event B occurs)
8. The idea of disjoint events is: is about whether or not it is possible for the
events to occur at the same time
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, 9. The idea of independent events is about: whether or not the events affect
each other in the sense that the occurrence of one event affects the probability
of the occurrence of the other
10. If A and B Disjoint: A and B can not be independent
11. If A and B are two independent events (Multiplication Rule): P(A and B) =
P(A) * P(B).
12. if A, B and C are three independent events,: P(A and B and C) = P(A) *
P(B) * P(C)
13. The Complement Rule,: P(A) = 1 - P(not A),
14. P(L) = 1 - P(not L) = 1 - P(not O1 and not O2 and not O3 and not O4 and
not O5 and not O6 and not O7 and not O8 and not O9 and not O10).:
Applying the Multiplication rule:Now, using the multiplication rule, = 1 - (.56 * .56
* .56 * .56 * .56 * .56 * .56 * .56 * .56 * .56) = 1 - .003 = .997.
15. P(at least one person chosen has blood type O): P((O and O) or (O and not
O) or (not O and O)) = (.44 * .44) + (.44 * .56) + (.56 * .44) = .6864.
16. If A and B are disjoint events -: P(A and B)= 0
17. The General Addition Rule states that for any two events,: P(A or B) =
P(A) + P(B) - P(A and B)
18. When each of two outcomes has two possible values (yes/no),: there
are four possible combinations altogether, which correspond to the four
possible outcomes.
19. How do we build a two-way table of probabilities?: Horizontally, A, not A
and total, Vertically, B. not B and total
20. In a two-way table of probabilities, what is the total of all outcomes
(lower right corner?): 1
21. Two events A and B are independent if any one of the following hold::
P(B | A)
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