Respuesta :

sqdancefan
There is 1 "R" among the 8 letters. Your probability is
  P(R) = 1/8
konrad509
I assume R means choosing a letter "r".

[tex]|\Omega|=8\\ |R|=1\\\\ P(R)=\dfrac{1}{8}\approx12.5\%[/tex]