Answer
It is not unusual to select a married couple at random for which only the wife works.
Work Step by Step
The sample space: 1700 married couples. So, N(S) = 1700
According to the marginal distribution (see definition, page 235) of the second row: N(only the wife works) = 126.
P(only the wife works) =
$\frac{N(\text{only the wife works})}{N(S)}=\frac{126}{1700}=\frac{63}{850}\approx0.074\gt0.05$
It is not unusual to select a married couple at random for which only the wife works.
