To find the ratio of the number of votes against the law to the number of votes in favor of the law, we first need to determine the number of votes against the law.
The total number of votes is 50, and the number of votes in favor of the law is 42. So, we can calculate the number of votes against the law as follows:
\[ \text{Votes against the law} = \text{Total votes} - \text{Votes in favor} \] \[ \text{Votes against the law} = 50 - 42 = 8 \]
Now we have:
- Votes in favor of the law = 42
- Votes against the law = 8
Next, we can establish the ratio of the number of votes against the law to the number of votes in favor of the law:
\[ \text{Ratio} = \frac{\text{Votes against the law}}{\text{Votes in favor of the law}} = \frac{8}{42} \]
To simplify this ratio, we can divide both the numerator and the denominator by their greatest common divisor (GCD), which is 2:
\[ \frac{8 \div 2}{42 \div 2} = \frac{4}{21} \]
Thus, the ratio of the number of votes against the law to the number of votes in favor of the law is
\[ \boxed{\frac{4}{21}}. \]