Out of the 150 people surveyed, 27 of them prefer mustard on a hot dog.
To estimate how many people out of the total 5,000 attendees prefer mustard, we can use proportions. We know that 27 out of 150 people prefer mustard, which is 18% of the sample. If we assume that the proportion of people who prefer mustard is the same in the entire population of 5,000 attendees, then we can estimate that:
0.18 x 5,000 = 900 people prefer mustard on a hot dog.
Therefore, based on the given data, an estimated 900 people in attendance would prefer mustard on a hot dog.