How many node does the final B-tree have?

Question

I'm currently studying the B-Trees chapter of Introduction to Algorithms. One of the question from the chapter is:

Suppose that we insert the keys $\{1,2,...,n\}$ into an empty B-tree with minimum degree 2. How many nodes does the final B-tree have?

I think given that a node will have between $t-1$ and $2t-1$ keys, where $t$ is the minimum degree, so the answer for this question will be somewhere between $n$ and $n/3$? This is where I'm stuck, any help would be appreciated.