Answer: 8/7752
Explanation:
Since we are told that the bag contains 5 red marbles, 8 white marbles, and 7 blue marbles. The total number fo marbles would be:
= 5 + 8 + 7
= 20 marbles
If 4 marbles out at random, without replacement, the probability that all the marbles are red would be:
= 5/20 × 4/19 × 3/18 × 2/17
= 1/4 × 4/19 × 1/6 × 2/17
= 8/7752