Answer:
[tex]\dfrac{4}{27}[/tex]
Step-by-step explanation:
A bag contains 8 blue marbles 6 red marbles and 4 green marbles, 8 + 6 + 4 = 18 marbles in total.
The probability of selecting a blue marble is
[tex]P(\text{blue marble})=\dfrac{\text{Number of blue marbles}}{\text{Total number of marbles}}=\dfrac{8}{18}=\dfrac{4}{9}[/tex]
Then the blue marble was replaced in the bag.
The probability of selecting a red marble is
[tex]P(\text{red marble})=\dfrac{\text{Number of red marbles}}{\text{Total number of marbles}}=\dfrac{6}{18}=\dfrac{1}{3}[/tex]
The probability of selecting a blue marble replaced it in the bag and then selecting a red marble is
[tex]P=\dfrac{4}{9}\cdot \dfrac{1}{3}=\dfrac{4}{27}[/tex]
