Option 1 : 900

Given:

Total voters = 5000

Winning candidate votes = 60% of valid votes

Invalid votes = 10% of total votes

Calculations:

Total Invalid votes = 5000 × (10/100) = 500

Total valid votes = 5000 – 500 = 4500

Winning candidate got 60% of valid vote = 4500 × (60/100) = 2700

Number of votes of Losing candidate = 4500 – 2700 = 1800

Difference between the votes of both candidates = 2700 – 1800 = 900

∴ The difference between the votes of both candidates is 900.