The problem is usually expressed as one of dividing a cake (or pie) and distributing it so that no-one is in a position to complain about the size of their slice ... There's this ... https://www.scientificamerican.com/article/the-mathematics-of-cake-cutting/ ... and then there's this by Ian Stewart https://www.amazon.co.uk/How-Cut-Cake-Mathematical-Conundrums/dp/0199205906 However, the best solution I know of (which Ian Stewart confirmed he had not heard of) came from the 13-year-old son of a colleague of mine .... Everyone gets a knife and makes a cut in a circular cake which is standing on a turntable ... with the aim of making equal-size slices. The cake is then spun, and everyone gets the slice opposite them. [ In other words, the randomness takes the decision about who gets what away from the hungry mathematicians ] Guy