Problem: How many supervisors were there? 3,300 or 3,600? 1 Kings 5:16 and 2 Chronicles 2:2
Solution: 3,300: 1 Kings 5:16, “besides Solomon’s 3,300 chief deputies who were over the project and who ruled over the people who were doing the work.”
3,600: 2 Chronicles 2:2, “So Solomon assigned 70,000 men to carry loads, and 80,000 men to quarry stone in the mountains, and 3,600 to supervise them.”
Either this is a copyist error or the people are being counted differently. If the people are being counted differently, it is interesting to note that the total number of supervisors is the same when we add the numbers from 1 Kings 5:16 and 1 Kings 9:23 together and also add 2 Chronicles 2:2 and 2 Chronicles 8:10 together.
However, the interesting problem is that in both places, the numbers are different, yet the totals are the same.
A comment worth noting is “In general it can be said that the books of Chronicles furnish approximate numerical estimates in the form of round numbers, frequently designed, as has been remarked, to express the magnitude of the occasion…Some estimates in Chronicles which appear to be particularly inflated can be corrected or scaled down by reference to the books of Samuel and Kings…However, it is not always the case that the figures in Chronicles exceed their counterparts in Samuel and Kings.”
 Harrison, R. K., Introduction to the Old Testament, Grand Rapids, MI: Eerdmans Publishing Company, 1969, p. 1165.