By this standard, Diaconis confirmed what Archimedes of Syracuse discovered more than 2,000 years ago: There are 30 families of fair dice. However, there are certain ways in which one die can be “more fair” than another.
What is unfair die?
An unfair die looks like an ordinary 4-sided die but the probability of a face landing on 2 is three times the probability of landing on 1. Similarly, the probability of landing on 3 is two times that of landing on 1 and the probability of landing on 4 is four times that of landing on 1.
Is a 10 sided die fair?
Though 10-sided dice are not Platonic solids, all of their faces are the same shape and size. This means that they are as fair as Platonic solids in any reasonable situation.
How do you know if a death is fair?
Place the die in the water, note which side of the die faces upwards, and then give it a flick. For reasonably balanced dice, you should see a good variety of numbers facing upwards. For badly balanced dice, you’ll probably see the same one or two faces regularly. Throw those bad dice out.