In a contest, two people will have to answer 110 questions each. They score 3 points for each correct answer. The contest has not ended yet. Each person has already answered 70 questions. Person X has answered 70% of the first 70 questions correctly. Person Y has answered 50% of the first 70 questions correctly. What is the minimum number of points that Person X must get from the last 40 questions to win the contest?

	Person X	Person Y
Current total score	147	105
Additional score if the remaining questions are answered correctly	+ 81	+ 120
Final total score	228	225
	Winner

Score that Person X has earned so far
= 70% x 70 x 3
= ⁷⁰₁₀₀ x 70 x 3
= 147

Score that Person Y has earned so far
= 50% x 70 x 3
= ⁵⁰₁₀₀ x 70 x 3
= 105

Remaining questions that each person has to answer
= 110 - 70
= 40

If Person Y answers the last 40 questions correctly, the additional score that he will earn
= 40 x 3
= 120

Total score that Person Y will earn after answering all the questions
= 105 + 120
= 225

Number of points that Person Y is leading Person X by
= 225 - 147
= 78

For Person X to win the contest, the number of points he has to earn
= 78 + 3
= 81

Answer(s): 81