Answer: The correct option is (A) 0.8.
Step-by-step explanation: Given that a large bag of marbles contains an equal amount of red, orange, yellow, blue, and green marbles. Brody randomly selects 1 marble from the bag.
We are to find the probability of selecting a red, blue, yellow or green marble.
Let n be the number of each color of marbles in the bag.
That is, the number of red, orange, yellow, blue, and green marbles, each equals n.
Let S denote the sample space of selecting a marble from the bag and A denote the event of selecting a red, blue, yellow or green marble.
Then, we have
n(S) = n + n + n + n + n = 5n,
n(A) = n + n + n + n = 4n.
Therefore, the probability of event A is given by
[tex]P(A)=\dfrac{n(A)}{n(S)}=\dfrac{4n}{5n}=\dfrac{4}{5}=0.8.[/tex]
Thus the required probability selecting a red, blue, yellow or green marble is 0.8.
Option (A) is CORRECT.
