Pizza Hut is taking the mildly interesting Pi Day and making it very interesting by giving away free pizza for 3.14 years. But there is a catch: you must first solve three math problems correctly from a mathematician from Princeton University.


The math questions hit the internet at 8 a.m. Wednesday from mathematician John H. Conway of Princeton University.

The first person to post the correct answers in the comments section of the blog post will win 3.14 years of free Pizza Hut products.

The official Twitter for the popular restaurant tweeted, “The pizza goes on and on and on and on.”

“Pi may be irrational, but free pizza is anything but,” Conway said in a statement. “I’m eager to challenge America with these problems and find the next great pizza-loving mathematician that can solve them.”

The questions are as follows:

  1.  Option A:
    I’m thinking of a ten-digit integer whose digits are all distinct. It happens that the number formed by the first n of them is divisible by n for each n from 1 to 10. What is my number?
  2. Option B:
    Our school’s puzzle-club meets in one of the schoolrooms every Friday after school.
    Last Friday, one of the members said, “I’ve hidden a list of numbers in this envelope that add up to the number of this room.” A girl said, “That’s obviously not enough That’s obviously not enough information to determine the number of the room. If you told us the number of numbers in the envelope and their product, would that be enough to work them all out?”
    He (after scribbling for some time): “No.” She (after scribbling for some more time): “Well, at least I’ve worked out their product.”
    What is the number of the school room we meet in?
  3. Option C:
    My key-rings are metal circles of diameter about two inches. They are all linked together in a strange jumble, so that try as I might, I can’t tell any pair from any other pair.
    However, I can tell some triple from other triples, even though I’ve never been able to distinguish left from right. What are the possible numbers of key-rings in this jumble?

“In celebration of National Pi Day, which pizza companies worldwide have sort of adopted as their own special holiday, Pizza Hut is marrying math and pizza in a one-of-a-kind challenge to find our most math-inclined fans and reward them with our great-tasting pizza,” said Doug Terfehr, senior director of public relations for Pizza Hut.

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