We need to determine what percentage of the surveyed people own fish.
From the survey data given in the relative frequency table, we know the following:
- The relative frequency of people who own both a bird and a fish is 0.04.
- The relative frequency of people who do not own a bird but own a fish is 0.08.
First, we calculate the total relative frequency of people who own fish by adding these two relative frequencies:
[tex]\[
\text{Relative frequency of owning fish} = 0.04 + 0.08 = 0.12
\][/tex]
The relative frequency 0.12 represents the proportion of the entire group of 150 customers. To find the percentage, we convert this relative frequency to a percentage by multiplying by 100:
[tex]\[
\text{Percentage of people who own fish} = 0.12 \times 100 = 12\%
\][/tex]
Thus, the percentage of people surveyed who own fish is:
[tex]\[
\boxed{12\%}
\][/tex]
