Marbles Combinations problem Martin’s bag of marbles contains two red, three blue and five green marbles. If     he reaches in to pick some without looking, how many different selections might he make?
I do not know how to approach this question. It asks if he were to pick some marbles. What does that mean?

Martin has $3$ choices for how many red. For he can choose $0$ or $1$ or $2$. For each of these choices, he has $4$ choices for how many blue, and then  $\dots$.
Remark: We assumed that marbles of the same colour are indistinguishable. We also assumed that the choice of no marbles is allowed. That is a matter of interpretation, since one could argue about the meaning of the word "some."
