Home > Resource of the Month Archive Detail

<< Prev 3/1/2015 Next >>

Throwing Hotdogs to Calculate Pi's Value

The web site tells it all. You actually can calculate an approximate value of pi by throwing a frozen hotdog. For those familiar with the history of mathematics, the hot dog experience is a slight variation of the Buffon Needle Experiment.

What is needed:

  • A frozen hot dog, or other food item such Otter Pops or celery sticks. Key requirements are that the food item be reasonably stiff and between six and eighteen inches long.
  • An open area big enough to accomodate a masking tape grid of parallel lines, with the distance apart being equal to the food item's length.
  • A recording sheet.
You then stand a reasonable distance away from the grid and throw the hot dog (or food item) unto the grid. Record the number of times that it lands touching a line and the number of times it is thrown. Repeat a minimum of 200 times...but temember the hot dog will be melting and losing its stiffness. The greater the number of tosses, the better the expected approximation!

Now, the calculation phase. Multiply the number of tosses by two and divide by the number of "line touches." For example, if the hot dog was thrown 200 times, and it crossed 128 times, the calculated value is (200 x 2)/128 = 3.125. Not a bad approximation for pi!

On the Cut-The-Knot website, Scott Brodie provides a good overview of the history of the Buffon Needle Experiment and the related mathematics. For more background, mathematics, simulations, and extensions, see the Website review again for this week.

Source: My thanks to Tim S. (Nooksack), who brought this web page to my attention.