Intern
Joined: 11 Feb 2020
Posts: 8
Concentration: Technology, Leadership
GPA: 3.72
WE:Engineering (Military & Defense)
Re: The probability that event M will not occur is 0.8 and the probability
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30 May 2021, 11:34
The probability that event M will not occur is 0.5 and the probability that event R will not occur is 0.5. If events M and R cannot both occur, which of the following is the probability that either event M or event R will occur?
P(M or R) = P(M) + P(R) - P(M and R)
P(M or R) = .5 + .5 - 0
P(M or R) = 1
I've changed the question to the probability instead being 0.5. Using the same solution method many have given here, I get a nonesense answer. I still do not see why the answer is not 11/25.