Answer
P(Sunday) $=\frac{12,547}{75,330}=0.167$
Work Step by Step
The sample space: 75,330 drivers involved in fatal crashes in the United States in 2009. So, N(S) = 75,330.
According to the marginal distribution (see definition, page 235) of the first row: N(Sunday) = 12,547.
P(Sunday) = $\frac{N(Sunday)}{N(S)}=\frac{12,547}{75,330}=0.167$
