Answer:
Minimum number of voters for the democratic candidate would be 3120 voters.
Explanation:
Total number of people turning out to vote = 12,000
Percentage of votes a democratic would get = 30%
Which means that it is expected that a democratic candidate will get: 30/100 · 12,000 = 3600 votes
However, the polling may have an error of +4% to -4%
Which means that the votes a democratic candidate will get will range from 30%+4% = 34% to 30%-4%= 26% of the total people who turn out to vote
Minimum number of voters can be determined by taking 26% of the total people who turn out to vote:
Minimum number of votes = 26/100 · 12,000 = 3120