Your answer, "40,000", is not correct.
The correct answer to
How many horse stalls did Solomon have?
is
4,000
as shown by
2 Chronicles 9:25
which is
- KJV
- And Solomon had four thousand stalls for horses and chariots, and twelve thousand horsemen; whom he bestowed in the chariot cities, and with the king at Jerusalem.
- NIV
- Solomon had four thousand stalls for horses and chariots, and twelve thousand horses, {Or charioteers} which he kept in the chariot cities and also with him in Jerusalem.