Answer
$\frac{1}{3}$
Work Step by Step
P(E) = $\frac{no.\ of\ outcomes\ in\ favor}{Total\ no\ of\ outcomes}$
S={1,2,3,4,5,6}, so there are 6 total outcomes.
There are 2 favorable outcomes (rolling a 1,2).
P(E) = $\frac{2}{6}$ = $\frac{1}{3}$