Hello, anthonye!

I have 16 marbles: 5 red, 11 blue.

I want to know the probability of getting 2 red and 2 blue when four are picked.

For the binomial I have:

which gives: . . ← This is incorrect.

Now for the combination: .

Don't understand why they have different answers.

Using the Binomial formula, the events are.independent

You are drawing the four marbles with replacement.