The statues differ a lot in size so you can't easily answer that question. The biggest are very close to the quarry. Many didn't even make it to their final destination, they got abandoned or broke on the way. The picture in the article which is very common is just below the quarry, some 400 statues got left there and approximately 1000 exist in total.
On the other side of the island some statues are only standing about 1m tall while the tallest (but unfinished) statues measures around 20m in height.
Putting the Pukao (hat) on some of the statues is also an additional complexity, they were made in a different quarry.