PSTAT 5LS Midterm 1 Exam 2026|2027 Questions with Detailed Verified Answers (100% Correct Answers) | Already Graded A+

PSTAT 5LS Midterm 1 Exam 2026|2027 Questions with
Detailed Verified Answers (100% Correct Answers) |
Already Graded A+


Rule #1 of Probability - Answer -The probability of an event A, denoted by P(A), is a number
between 0 and 1.




Rule #2 of Probability - Answer -In a random experiment, the probability of all the outcomes
added together is 1.




Conditional Probability - Answer -the probability of an event occurring given that another event
has already occurred




Rule #3 of Probability - Answer -2 events are mutually exclusive if they cannot occur at the same
time




Rule #4 of Probability - Answer -P(A^c)=1-P(A)




Rule #5 of Probability - Answer -for overlapping events:

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



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, Mutually Exclusive Events - Answer -cannot occur at the same time:

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




Independence - Answer -the occurrence of one event does not affect the probability of
occurrence of the other




Multiplication Rule - Answer -The probability that events A and B happen together:P(A and B) =
P(B | A)P(A)




Rule #6 of Probability - Answer -for independent events:

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




Tree Diagram - Answer -




Difference Between ME and Independent - Answer -If A and B are ME then A prevents B so
P(B|A)=0, so they are not independent.




Theoretical Probability - Answer -from understanding the phenomenon and symmetries in the
problem




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