kelly chooses marbles from a bag to give to her friends. the probability that she picks a red marble first…

kelly chooses marbles from a bag to give to her friends. the probability that she picks a red marble first is 0.25. the probability that she picks a red marble first and a blue marble second is 0.20. what is the probability that kelly chooses a blue marble second, given that she chose a red marble first? enter the answer in the box.

kelly chooses marbles from a bag to give to her friends. the probability that she picks a red marble first is 0.25. the probability that she picks a red marble first and a blue marble second is 0.20. what is the probability that kelly chooses a blue marble second, given that she chose a red marble first? enter the answer in the box.

Answer

Explanation:

Step1: Recall conditional - probability formula

The formula for conditional probability is $P(B|A)=\frac{P(A\cap B)}{P(A)}$, where $P(B|A)$ is the probability of event $B$ occurring given that event $A$ has occurred, $P(A\cap B)$ is the probability of both $A$ and $B$ occurring, and $P(A)$ is the probability of event $A$ occurring. Let event $A$ be picking a red marble first and event $B$ be picking a blue marble second. We know that $P(A) = 0.25$ and $P(A\cap B)=0.20$.

Step2: Substitute values into the formula

$P(B|A)=\frac{P(A\cap B)}{P(A)}=\frac{0.20}{0.25}$

Step3: Calculate the result

$\frac{0.20}{0.25}=\frac{20}{25}=\frac{4}{5} = 0.8$

Answer:

$0.8$