Basic Probablity

Factual Questions
1

From a bag of 5 red, 4 gold and 6 green marbles, what is the probability of reaching in and getting 3 gold marbles if you do not replace the marbles
between selecting them? Give your answer as a fraction in lowest terms.

When I do it I get 4/15 x 3/14 x 2/13 =4/455. Is this answer correct?

2

yes

3

That is correct. For reference, this sort of problem is very easily solved by using the hypergeometric distribution. Here you’re looking to compute f(3; 15, 4, 3).