I don't think the calculation says anything about the grouping of data. Or does it? If you have an unbiased sample of 584 votes and 60% of the sample responde

I don't think the calculation says anything about the grouping of data. Or does it? If you have an unbiased sample of 584 votes and 60% of the sample responded "25 - 30", could you say with 95% confidence that 60% (+/-4%) of the sampled population would select "25 - 30"?