If the Bible is 100% accurate, it is accurate in a different sense than we would apply to other books.
Studies of Wikipedia and the Encyclopedia Britannica found an average of one serious error per ten articles (each)--this number is not stated but can be calculated from numbers given here. An article is usually a few hundred words (exactly how many depends on the edition), so that's a serious error every few thousand words.
Unfortunately, most of the events described in the Bible are hard to rigorously validate, unlike encyclopedias where most every statement can be validated. Nonetheless, we can attempt to validate the Bible against itself by comparing a straightforward interpretation (as one would use with an encyclopedia) of different passages in the Bible.
The best opportunity to do this is with the Gospels since they all describe the same period of time. Thus, we can use them for cross-validation (when interpreted plainly as a historical account).
Matthew 1:16 (ESV) explains:
and Jacob the father of Joseph the husband of Mary, of whom Jesus was born, who is called Christ.
But Luke 3:23 (ESV) instead says:
Jesus, when he began his ministry, was about thirty years of age, being the son (as was supposed) of Joseph, the son of Heli,
Joseph is presumably not the son of both Heli and Jacob, so at least by the standards used with encyclopedias*, this is an error.
According to Matthew 2:13-15 (ESV), Jesus spent some time in Egypt (immediately following a visit by the wise men):
13Now when they had departed, behold, an angel of the Lord appeared to Joseph in a dream and said, "Rise, take the child and his mother, and flee to Egypt, and remain there until I tell you, for Herod is about to search for the child, to destroy him." 14And he rose and took the child and his mother by night and departed to Egypt 15and remained there until the death of Herod. This was to fulfill what the Lord had spoken by the prophet, "Out of Egypt I called my son."
Luke, on the other hand, seems to indicate that Jesus never left (Luke 2:21-42 are all relevant, in but brief):
21And at the end of eight days, when he was circumcised, he was called Jesus, the name given by the angel before he was conceived in the womb. 22And when the time came for their purification according to the Law of Moses, they brought him up to Jerusalem to present him to the Lord
So within about 5000 words, we have one assuredly contradictory account and one probable contradiction--no better than encyclopedias (and perhaps worse, since this is not an exhaustive survey, and many accounts cannot be confirmed).
Thus, claims that the Bible is 100% accurate, if correct, cannot mean that it's 100% accurate in the way you would expect an encyclopedia to be 100% accurate.
*There is a "Levirate marriage" explanation for the discrepancy, but we generally don't expect encyclopedias to require us to go to so much trouble to figure out what is being said. Also, there's Ram vs. Arni and Admin in the Abraham to David line; Ruth agrees with Matthew, not Luke on this.
