Question 694847
The probability of Not drawing a "c" is 
1 - the probability of drawing a "c".
since there are 13 letters and only 1 of them is  "c",
the probability of drawing a "c" is {{{1/13}}}
therefore 
the probability of Not drawing a "c" = {{{1 - (1/13)}}}
which ={{{12/13}}}