In an experiment, the probability that event A occurs is 73, the probability that event B occurs is 21, and the probability that events A and B both occur is 83. 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 73, the probability that event B occurs is 21, and the probability that events A and B both occur is 83. 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)=83 and P(B)=21.
Multiply Fractions: Now, let's do the calculation: P(A∣B)=83/21.
Simplify Multiplication: To divide by a fraction, we multiply by its reciprocal. So, P(A∣B)=83×12.
Reduce Fraction: Multiplying the fractions, we get P(A∣B)=8×13×2.
Final Probability: Simplifying the multiplication, P(A∣B)=86.
Final Probability: Simplifying the multiplication, P(A∣B)=86.We can reduce the fraction 86 by dividing both numerator and denominator by 2.
Final Probability: Simplifying the multiplication, P(A∣B)=86.We can reduce the fraction 86 by dividing both numerator and denominator by 2.After simplifying, we get P(A∣B)=43.