Answer :
You have the next set of possible chosen cards:
[tex]\begin{gathered} \lbrace1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17\rbrace \\ \end{gathered}[/tex]A total of: 17
You have the next set of odd number:
[tex]\lbrace1,3,5,7,9,11,13,15,17\rbrace[/tex]Odd number: 9
Then, the probability of choose an odd number is: 9/17[tex]P=\frac{9}{17}[/tex]