The probability that event M will not occur is 0.8 and the probability that event R will not occur is 0.6. If events M and R cannot both occur, which of the following is the probability that either event M or event R will occur?
A) 1/5
B) 2/5
C) 3/5
D) 4/5
E) 12/25
OA is c
I solved this question twice and I got two answers, can someone confirm if it is C or A
Probability
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Hello Roland2rule.
The question tell us that the probability that event M will NOT occur is 0.8, it implies that the probability that event M will OCCUR is 0.2.
Also, as the probability that event R will NOT occur is 0.6, then the probability that event R will OCCUR is 0.4.
Finally, it is asked what is the probability that either event M or event R will occur, so, the probability is the sum of the two probabilities calculated before. That is to say,
$$P\left(M\right)+P\left(R\right)=0.2+0.4\ =\ 0.6\ =\ \frac{3}{5}.$$
So, the correct answer is C .
I hope this can help you.
Feel free to ask me again if you have a doubt.
The question tell us that the probability that event M will NOT occur is 0.8, it implies that the probability that event M will OCCUR is 0.2.
Also, as the probability that event R will NOT occur is 0.6, then the probability that event R will OCCUR is 0.4.
Finally, it is asked what is the probability that either event M or event R will occur, so, the probability is the sum of the two probabilities calculated before. That is to say,
$$P\left(M\right)+P\left(R\right)=0.2+0.4\ =\ 0.6\ =\ \frac{3}{5}.$$
So, the correct answer is C .
I hope this can help you.
Feel free to ask me again if you have a doubt.
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BTGmoderatorRO wrote:The probability that event M will not occur is 0.8 and the probability that event R will not occur is 0.6. If events M and R cannot both occur, which of the following is the probability that either event M or event R will occur?
A) 1/5
B) 2/5
C) 3/5
D) 4/5
E) 12/25
OA is c
I solved this question twice and I got two answers, can someone confirm if it is C or A
We are given that the probability that event M will not occur is 0.8 and the probability that event R will not occur is 0.6, and that events M and R cannot both occur.
We need to determine the probability that either event M or event R will occur.
The probability that event M will occur is 1 - 0.8 = 0.2 = 1/5
The probability that event R will occur is 1 - 0.6 = 0.4 = 2/5
Recall that the formula for the probability of event A or event B occurring is P(A or B) = P(A) + P(B) - P(A and B); therefore:
P(M or R) = P(M) + P(R) - P(M and R).
Since we are told that events M and R cannot both occur, that means P(M and R) = 0, and thus the probability that either event M or event R will occur is:
P(M or R) = 1/5 + 2/5 - 0 = 3/5.
Answer: C
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