UPSC CAPF AC 2017 Paper

We know that if two candidate contested in an election and one candidate get x%of total votes casted and still lose by y votes, then
Total number of votes casted =

100×y

100−2x

Here, total number of votes casted = 4000, y = ?, x= 40%
∴ 4000=

100×y

100−2×40

⇒ 4000=

100×y

100−80

⇒4000=5y⇒ y=800
∴ Margin of defeat = 800 votes