Answer
$P(E)=\frac{1}{19}\approx0.05263$.
If we play the game 1900 times, we would expect that the metal ball falls into a green slot about 100 times.
Work Step by Step
The sample space S = {0, 00, 1, 2, 3, ..., 34, 35, 36}. So, $N(S)=38$
Let E be the event "green slot" = {0, 00}. So, $N(E)=2$.
$P(E)=\frac{N(E)}{N(S)}=\frac{2}{38}=\frac{1}{19}\approx0.05263$
