Probability mutual exclusive homework problem

AI Thread Summary
For independent events A and B, with probabilities p(A) = 0.6 and p(B) = 0.7, the probability of both A and B occurring is calculated by multiplying their probabilities, resulting in 0.42. To find the probability of A or B, one must consider the probabilities of A only, B only, and both A and B. The probability of A only is 0.18, B only is 0.28, and both A and B is 0.42, leading to a total probability of A or B as 0.88. The discussion clarifies the relationship between independent and mutually exclusive events in probability. Understanding these concepts is crucial for solving similar problems effectively.
Sombra
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Given that p(A)=0.6 and p(B)= 0.7 and that A and B are independent, find the probabilty of
a. A or B
b. A and B

I don't understand this because if 2 events are independent, then they are not mutually exclusive. So, A and B does not = 0, but that's all I know and I need A and B to solve for A or B. Help! Thanks
 
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Originally posted by Sombra
Given that p(A)=0.6 and p(B)= 0.7 and that A and B are independent, find the probabilty of
a. A or B
b. A and B
b).
Just multiply the two together.
(0.6)(0.7) = 0.42

a).
For this one you have to find the probability of A only, B only, A and B. Then you just add those.
A only:
(0.6)(1-0.7) = 0.18
B only:
(1-0.6)(0.7) = 0.28
A and B:
(0.6)(0.7) = 0.42

Sum of those:
0.18 + 0.28 + 0.42 = 0.88
 
Last edited:


¡Muchas gracias! That helped a lot
 
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