In an experiment, the probability that event A occurs is 21, the probability that event B occurs is 43, and the probability that events A and B both occur is 72. What is the probability that A occurs given that B occurs? Simplify any fractions.
Q. In an experiment, the probability that event A occurs is 21, the probability that event B occurs is 43, and the probability that events A and B both occur is 72. What is the probability that A occurs given that B occurs? Simplify any fractions.
Use Conditional Probability Formula: To find the probability that A occurs given that B occurs, we use the formula for conditional probability: P(A∣B)=P(B)P(A and B).
Calculate P(A∣B): We know P(A and B)=72 and P(B)=43. So, P(A∣B)=4372.
Multiply Fractions: To divide the fractions, we multiply by the reciprocal of the second fraction: (72)×(34).
Simplify the Result: Now, multiply the numerators and denominators: (2×4)/(7×3)=8/21.