Question 1116373
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<pre>
2 + 1 + 1 + 22 = 26 is the total number of envelopes.


The probability to select the (unique) blue of the total 26 envelopes is {{{1/26}}} at the first selection, 

and it is the same {{{1/26}}} at the second selection after replacement.


So the answer is {{{1/26^2}}}.
</pre>

Solved.