Well, the original source of the error was somebody the WSJ quoted, but they took it the next step without correction:
Until recently, for instance, the Lincoln Navigator offered 128 options on its console alone.
“You know what 128-factorial is—it’s a lot of combinations,” Mr. Mulally joked at a conference recently, mocking the number of designs theoretically resulting from mixing-and-matching the options. (Answer: 3.85620482 x 10 to the 215th power.)
Spector, Mike. “Ford Eyes More Cuts as Recovery Advances; Earnings Improve”. The Wall Street Journal 23 April 2008: A1, A14.
128-factorial is the correct number of combinations of options only if the order in which you pick the options is important. It almost certainly is not. Instead, assuming each option is independent and can be either on or off, the correct number of combinations is 2^128—3.4 x 10^38. Mr. Mulally was off by a factor of 177.
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