Problem:
Two dice are loaded so that the numbers through come up with various (possibly different) probabilities on each die. Is it possible that, when both dice are rolled, each of the possible totals through has an equal probability of occurring?
Problem:
Two dice are loaded so that the numbers through come up with various (possibly different) probabilities on each die. Is it possible that, when both dice are rolled, each of the possible totals through has an equal probability of occurring?
Solution:
The answer is no. Suppose that each of the totals from to has an equal probability, which must be since the sum of all probabilities is . Let and be the probabilities of a and a , respectively, on the first die, and let and be the corresponding probabilities on the second die.
Since is the probability of rolling a total of , so ; since is the probability of rolling , so . Since the probability of rolling a through the combination or is at most ,
Since and are reciprocals, one of them is at least , so this inequality cannot hold.