How Do You Calculate the Probability of Both Events Occurring?

AI Thread Summary
To calculate the probability of both Mr. Jones and Mr. Smith being selected for jury duty, the relevant probabilities are P(A) = 0.7, P(B) = 0.4, and the probability that neither is selected, P(A^c ∩ B^c) = 0.1. Using the formula P(A^c ∩ B^c) + P(A ∪ B) = 1, one can derive P(A ∪ B) = 0.9. The "and" rule is also applicable here to find P(A ∩ B). Ultimately, the discussion emphasizes the importance of understanding basic probability concepts for solving such problems effectively.
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Homework Statement



The probability of Mr. Jones being selected for jury duty is 70%. The probability that Mr. Smith will be selected is 40%. The probability that neither will be selected is 10%. What is the probability that both are selected?

Homework Equations



the "and" rule

The Attempt at a Solution



(.4) + (.7) - (.1) = 1
 
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first of all i think you should get a good book on probability since most of the problems posted by you are quite basic and you seem to be guessing the answers..

in this question

given is

P(A) = 0.7
P(B) = 0.4
P(A^{c}\capB^{c})= 0.1

you have to find P(A\capB)

use

P(A^{c}\capB^{c}) + P(A\cupB) =1
 
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