What is the maximum number of records that can be indexed in B+ tree of level $4$ ,order $10$ where root is at level $1$ ?
As the order of tree is $10$, nodes in the last level of b+ tree should contain $10$ record pointers (number of record pointers = order of leaf node). So I think that answer should be $ \big(10\big) \big(10\big) \big(10\big)\big(10\big)= 10,000$.
But the answer given is $\big(10\big)\big(10\big)\big(10\big)\big(9\big) = 9000$ considering that leaf nodes contain only $10-1 = 9$ record pointers.
Which one is correct?