Question

A bag contains 5 red marbles and 4 green marbles.

Answer 1

Answer:  The required probability is $\dfrac{5}{18}.$

Step-by-step explanation:  Given that a bag contains 5 red marbles and 4 green marbles.

We are to find the probability of choosing a red marble then a green marble, without replacement.

Total number of balls in the bag = 5 + 4 = 9.

The probability of choosing a red marble is given by

$P_r=\dfrac{\textup{number of red balls}}{\textup{total number of balls}}=\dfrac{5}{9}.$

Since the second balls is chosen without replacing the first ball, so

the total number of balls remained in the bag = 4 + 4 = 8.

And the probability of choosing a green ball without replacement is

$P_g=\dfrac{\textup{number of green balls}}{\textup{total number of balls remained in the bag}}=\dfrac{4}{8}=\dfrac{1}{2}.$

Therefore, the probability of choosing a red marble then a green marble, without replacement is given by

$P=P_r\times P_g=\dfrac{5}{9}\times \dfrac{1}{2}=\dfrac{5}{18}.$

Thus, the required probability is $\dfrac{5}{18}.$

Answer 2

The probability of choosing a red marble then a green marble without replacement would be around 5/14