Conditional Probability
IBprobabilityunit.notebook
October 13, 2015
OBJECTIVE: SWBAT compute conditional probability. Do Now: Urn A contains 2 red and 3 blue marbles. Urn B contains 4 red and 1 blue. Peter selects what urn he will pick from by flipping a coin. a)Create a tree diagram to represent this
b) Find the P(red) c) P(red, given urn b)
HW #20: circled problems on Conditional probability worksheet
Sep 302:55 PM
Conditional Probability A|B is used to represent that “A occurs knowing that B has occurred” P(A│B) = P(A∩B) P(B)
Oct 217:15 AM
1
IBprobabilityunit.notebook
October 13, 2015
In a factory 3 operators A, B, and C work on a certain machine. The number of parts produced by A, B, and C are 25%, 40%, and 35% respectively. The percentage of defectives produced is 1% for A, 1.5% for B, 3% for C. A part is chosen at random. Determine the probability that:
a) it is defective
b) it is defective given that it was produced by B
c) it was produced by B given that it is defective
Oct 207:50 AM
Oct 1611:20 AM
2
October 13, 2015
OBJECTIVE: SWBAT compute conditional probability. Do Now: Urn A contains 2 red and 3 blue marbles. Urn B contains 4 red and 1 blue. Peter selects what urn he will pick from by flipping a coin. a)Create a tree diagram to represent this
b) Find the P(red) c) P(red, given urn b)
HW #20: circled problems on Conditional probability worksheet
Sep 302:55 PM
Conditional Probability A|B is used to represent that “A occurs knowing that B has occurred” P(A│B) = P(A∩B) P(B)
Oct 217:15 AM
1
IBprobabilityunit.notebook
October 13, 2015
In a factory 3 operators A, B, and C work on a certain machine. The number of parts produced by A, B, and C are 25%, 40%, and 35% respectively. The percentage of defectives produced is 1% for A, 1.5% for B, 3% for C. A part is chosen at random. Determine the probability that:
a) it is defective
b) it is defective given that it was produced by B
c) it was produced by B given that it is defective
Oct 207:50 AM
Oct 1611:20 AM
2
