Flipping Coins, Mortgage Defaults, and 'Sesame Street'


There are, of course, many other indications of politicians' innumeracy. A recent example: some of the tax claims made during the campaign, based as they are on quite dubious assumptions. And suggesting that cutting programs like "Sesame Street" will do much to reduce the deficit is similarly clueless. There are countless such examples. To counter them it helps to remember that arithmetic and probability are two of our most basic reality principles and, to the extent they're misunderstood, our political and other choices will be distorted.

Extra Credit: You flip a coin 10 times and roll a die 4 times. What's more likely: the coin will come up heads all 10 times or the die will turn up 6 all 4 times?

John Allen Paulos, a professor of mathematics at Temple University in Philadelphia, is the author of several best-selling books, including "Innumeracy," "A Mathematician Reads the Newspaper" and "A Mathematician Plays the Stock Market." He's on Twitter and his "Who's Counting?" column on ABCNews.com appears occasionally here. This work is the opinion of the columnist and in no way reflects the opinion of ABC News.

Answer: The probability of 10 consecutive heads is (1/2)^10 or 1/1,024, which is higher than the probability of 4 straight 6s, which is (1/6)^4 or 1/1,296.

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