Correct option is A
Given:
90% of registered voters voted.
15% of votes polled were invalid.
Winning candidate got 51% of valid votes.
Margin of victory = 2142 votes.
Find total registered voters
Formula Used:
Valid votes = (Total votes polled) × (1 − invalid %)
Solution:
Let total registered voters = N
Votes polled = 0.90N
Valid votes = 0.90N × 0.85 = 0.765N
Margin = (51% − 49%) of valid votes = 2% of valid votes
0.02 × 0.765N = 2142
0.0153N = 2142
N = = 140000