The money in 2 evelopes "paradox"

[Ra_]

let the two amounts be A and 2A

I think argument 1 only holds true if A is randomly selected
so that 0<A<inf, where a A can be any positive number where A mod 0.01 = 0. If this is the case there is a greater than 99.99999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 9999999
percent chance that A is greater than
10000000000000000000000000000000000000000000000000 00000000000000000000000000000000000000000000000000 00000000000000000000000000000000000000000000000000 0000000
so i dont think it matter which envelope you pick, because your expected value is near infinity.

If A has a finite number of values or a finite range
(unknown to you) then i think your EV is predetermined no
matter your desision.

imagine you give this challenge to a million people using
A=50 and to a million people using A=100. Your EV =
-75,000,000 - 150,000,00 = -225,000,000. assuming people
always try to switch.

Edited to make A only even cents.