WGU STATISTICS EXAM 2025
QUESTIONS AND ANSWERS
The probability of any event is between one and o. What is the equation for this? - ANS For
any event A, 0 ≤ P(A) ≤ 1.
The sum of all possible probabilities is___? - ANS One, the equation is :P(S) = 1
What is the complement rule? or the probability that an event does not occur is 1 minus the
probability that it does occur. - ANS P(not A) = 1 - P(A)
In probability, "OR" means either one or the other or both. - ANS P(A or B) = P(event A
occurs or event B occurs or both occur)
Two events that cannot occur at the same time are called - ANS disjoint or mutually exclusive
The Addition Rule for Disjoint Events: - ANS If A and B are disjoint events, then P(A or B) =
P(A) + P(B).
P(A and B) = - ANS P(event A occurs and event B occurs)
The idea of disjoint events is - ANS is about whether or not it is possible for the events to
occur at the same time
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, The idea of independent events is about - ANS 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
If A and B Disjoint - ANS A and B can not be indepentdent
If A and B are two independent events (Multiplication Rule) - ANS P(A and B) = P(A) * P(B).
if A, B and C are three independent events, - ANS P(A and B and C) = P(A) * P(B) * P(C)
The Complement Rule, - ANS P(A) = 1 - P(not A),
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). - ANS Applying the Multiplication rule:Now,
using the multiplication rule, = 1 - (.56 * .56 * .56 * .56 * .56 * .56 * .56 * .56 * .56 * .56) = 1 -
.003 = .997.
P(at least one person chosen has blood type O) - ANS P((O and O) or (O and not O) or (not O
and O)) = (.44 * .44) + (.44 * .56) + (.56 * .44) = .6864.
If A and B are disjoint events - - ANS P(A and B)= 0
The General Addition Rule states that for any two events, - ANS P(A or B) = P(A) + P(B) - P(A
and B)
When each of two outcomes has two possible values (yes/no), - ANS there are four possible
combinations altogether, which correspond to the four possible outcomes.
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QUESTIONS AND ANSWERS
The probability of any event is between one and o. What is the equation for this? - ANS For
any event A, 0 ≤ P(A) ≤ 1.
The sum of all possible probabilities is___? - ANS One, the equation is :P(S) = 1
What is the complement rule? or the probability that an event does not occur is 1 minus the
probability that it does occur. - ANS P(not A) = 1 - P(A)
In probability, "OR" means either one or the other or both. - ANS P(A or B) = P(event A
occurs or event B occurs or both occur)
Two events that cannot occur at the same time are called - ANS disjoint or mutually exclusive
The Addition Rule for Disjoint Events: - ANS If A and B are disjoint events, then P(A or B) =
P(A) + P(B).
P(A and B) = - ANS P(event A occurs and event B occurs)
The idea of disjoint events is - ANS is about whether or not it is possible for the events to
occur at the same time
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, The idea of independent events is about - ANS 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
If A and B Disjoint - ANS A and B can not be indepentdent
If A and B are two independent events (Multiplication Rule) - ANS P(A and B) = P(A) * P(B).
if A, B and C are three independent events, - ANS P(A and B and C) = P(A) * P(B) * P(C)
The Complement Rule, - ANS P(A) = 1 - P(not A),
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). - ANS Applying the Multiplication rule:Now,
using the multiplication rule, = 1 - (.56 * .56 * .56 * .56 * .56 * .56 * .56 * .56 * .56 * .56) = 1 -
.003 = .997.
P(at least one person chosen has blood type O) - ANS P((O and O) or (O and not O) or (not O
and O)) = (.44 * .44) + (.44 * .56) + (.56 * .44) = .6864.
If A and B are disjoint events - - ANS P(A and B)= 0
The General Addition Rule states that for any two events, - ANS P(A or B) = P(A) + P(B) - P(A
and B)
When each of two outcomes has two possible values (yes/no), - ANS there are four possible
combinations altogether, which correspond to the four possible outcomes.
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