How Do You Calculate the Probability of Both Events Occurring?

[Calculator14]

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

 

[the_amateur]

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}$$\cap$B$^{c}$)= 0.1

you have to find P(A$\cap$B)

use

P(A$^{c}$$\cap$B$^{c}$) + P(A$\cup$B) =1