Answer: The required probability that Colin wins is 50%.
Step-by-step explanation: Given that Ella created a board game that instructs players to roll a standard 6-sided number cube and pick a marble out of a bag without looking.
On Colin's turn, the bag contains 1 red marble, 1 blue marble, and 1 green marble.
We are to find the probability that Colin wins the game if he can win the game by either rolling a "6" or choosing the red marble.
Let S denote the sample space for the experiment of rolling a die and A denote the event of rolling a 6.
Then, n(S) = 6 and n(A) = 1.
Again, let S' denote the sample space for the experiment of selecting a marble from the bag with 1 red marble, 1 blue marble and 1 green marble
and B denote the event of selecting a red marble.
Then, n(S') = 3 and n(B) = 1.
Therefore, the probability that Colin wins the game will be

Thus, the required probability that Colin wins is 50%.