Find the probability of getting a real "bust" hand in poker. A "bust" hand has no pair and is neither a straight, a flush, a straight flush nor a royal flush. [The ranking of poker hands from high to low is royal flush, straight flush, four of a kind, full house, flush, straight, three of a kind, two pairs, one pair, and, in the case of a bust hand, the highest ranked single card. Since single cards are ranked ace, king, queen, jack, $10,9, \ldots, 2$ without regard to suit, the best bust hand is an "ace high."]