Answer
$P(E)=\frac{18}{38}\approx0.474$. It means that, if we play the game 3800 times, we would expect that the metal ball lands in an odd slot about 1800 times.
Work Step by Step
E = "odd slot" = [1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35]. There are 18 odd slots: N(E) = 18.
$P(E)=\frac{N(E)}{N(S)}=\frac{18}{38}\approx0.474$