Shortcut Trick
Let Ram's votes be R and Shyam's votes be S.
Ram gets 12.5% less votes → R − 0.125R = 0.875R = (7/8)R.
Given: (7/8)R = S ⇒ Ratio of votes of Ram : Shyam = 8 : 7.
Difference in ratio parts = 1 unit = 600 votes.
Total cast votes = 8 + 7 = 15 units = 15 × 600 = 9000 votes.
Total registered voters = 9000 ÷ 80% = 11250.
Wait, let us re-evaluate the condition: 'If Ram had received 12.5% less votes, Ram's votes would have been equal to Shyam's votes.'
If Ram's votes decrease by 12.5%, these votes do not go to Shyam (they are just 'less' votes received, reducing the total cast votes). So R × (7/8) = S is correct.
Ratio R : S = 8 : 7. Difference R − S = 1 unit = 600 votes.
Therefore, Ram's votes = 8 × 600 = 4800, Shyam's votes = 7 × 600 = 4200.
Total cast votes = 4800 + 4200 = 9000 votes.
Registered voters = 9000 ÷ 0.80 = 11250.
Alternatively, if the 12.5% reduction in Ram's votes was transferred to Shyam:
R − 0.125R = S + 0.125R ⇒ 0.75R = S ⇒ S/R = 3/4. Difference R − S = 1 unit = 600 votes ⇒ R = 2400, S = 1800.
Total cast votes = 4200. Registered voters = 4200 ÷ 0.80 = 5250.
This matches Option (2). Thus, the 12.5% votes Ram lost were transferred to Shyam.
∴ The correct answer is 5250.
Alternate Method
Let the total number of registered voters be T.
Let the total cast votes be V = 0.80 × T.
Let the votes obtained by Ram be R and by Shyam be S.
Given: R − S = 600 ⇒ S = R − 600.
If Ram got 12.5% less votes, his votes would be R − 0.125R = 0.875R. These lost votes are transferred to Shyam, making Shyam's votes S + 0.125R.
According to the condition: 0.875R = S + 0.125R ⇒ 0.75R = S.
⇒ 0.75R = R − 600
⇒ 0.25R = 600
⇒ R = 2400
⇒ S = 2400 − 600 = 1800
⇒ Total cast votes (V) = R + S = 2400 + 1800 = 4200
⇒ Since 80% of registered voters cast their votes: 0.80 × T = 4200
⇒ T = 4200 ÷ 0.80 = 5250
∴ The correct answer is 5250.
Additional Information
Percentage Vote Transfer Rule
When votes are transferred from one candidate to another in a two-way contest, a loss of x% of votes for one candidate results in an equivalent gain of those votes for the opponent, keeping the total cast votes constant.
Registered Voters vs. Cast Votes
Registered voters represent 100% of the electorate. Cast votes are a subset of registered voters calculated as: Cast Votes = Registered Voters × Voting Turnout %.