10 % of the electorate did not cast their votes in an election between two candidates. 10 % of the votes polled were found invalid. The successful candidate got 54 % of the valid votes and won by a majority of 1620 votes. The number of voters enrolled on the voter's list was___________?
Correct answer: A. 25000
- A. 25000
- B. 33000
- C. 35000
- D. 40000
Explanation
If the electorate is E voters, votes polled are 90% of E and valid votes are 90% of those, so valid votes = 0.90 × 0.90E = 0.81E votes. The winner's margin is (54% − 46%) × 0.81E = 0.08 × 0.81E = 0.0648E votes; setting this equal to 1,620 votes gives E = 1,620 ÷ 0.0648 = 25,000 voters. The likely mistake is using 8% of the electorate directly and ignoring the non-voters and invalid votes.
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