in an election about 500,000 people voted in all which number could be the exact number of people who voted in the election

I think this question is asking for the closest number to 500,000, which is 533,736. I don't know how to show work for this, except for saying this number is about 33,000 away from 500,000 which is the closest out of 429,455, 441,689, 533,736, and 550,198.