4*2=8

3*3=9

3*2=6 ]]>

For example, say two sets of envelopes were prepared, one set with $10 and $20, and the other with $20 and $40. Then they are shuffled, and only one set is given to Gerry. If he opens it and finds $20, the expected value in the other envelope is indeed $25. But if he finds $10 to $40, the other envelope is certain to contain $20.

The point of the paradox, is that Gerry’s solution assumes that the distribution of possible envelopes is uniform over all values from 0 to infinity, which is not possible. This can be easier to understand if you add a third envelope to my set (with $40 and $80), then a fourth, etc. Gerry’s solution will always be correct, except for the lowest and highest possible values.

]]>2) MONTANA ]]>