Spaghetti holes

I want to make one of those measuring tools for spaghetti. ItÕs a board with holes of various sizes in it. ThereÕs a hole through which you stick enough spaghetti to feed 2 people, another hole for 3 servings, another for 4. I know that the hole for 2 servings has a diamter of 1 inch. How large should the other holes be?


guess and check

find area for 1 person, then set up and solve equaations for other numbers of people

area ratios: diameter of hole for 3 servings is the square root of 3/2 times the diameter of the hole for 2 people.

see pattern in data for 1, 2, 3, 4 servings, note constant second differences, find quadratic function for prediction

Does pattern hold for 0 servings?

Your experience

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Last updated 30 November, 2004