What do inerrancy and infallibility really mean when it comes to specific verses?

Q: Battles loom large over the definitions of inerrancy and infallibility. What do these terms really mean when it comes to specific verses? For instances, some will say it’s an error when the Bible uses round numbers for how many are in a tribe, or for the number of people killed in a battle. When the text uses specific numbers in other places, or when one gospel account has Jesus calling for a single donkey to be brought to Him and He says, “bring it to me” – versus calling for a donkey and the foal of a donkey – “bring them to me.” Or they’ll cite the last two verses of 2 Chronicles, which duplicates the opening verses of Ezra exactly but cuts off the command of Cyrus mid-sentence, losing the gist of his command.  Obviously God didn’t inspire the writer of chronicles to do that, there was an error of transmission over the centuries, and part of Ezra was copied into Chronicles.  I’ve heard good theologians say, and I tend to agree, that scripture is accurate and dependable enough for the purpose for which its intended, but to insist that every word, every description, every story is perfect down to the molecular level leads to unnecessary controversies.