In a contest, two people will have to answer 110 questions each. They score 4 points for each correct answer. The contest has not ended yet. Each person has already answered 90 questions. Person J has answered 70% of the first 90 questions correctly. Person K has answered 50% of the first 90 questions correctly. What is the minimum number of points that Person J must get from the last 20 questions to win the contest?

	Person J	Person K
Current total score	252	180
Additional score if the remaining questions are answered correctly	+ 12	+ 80
Final total score	264	260
	Winner

Score that Person J has earned so far
= 70% x 90 x 4
= ⁷⁰₁₀₀ x 90 x 4
= 252

Score that Person K has earned so far
= 50% x 90 x 4
= ⁵⁰₁₀₀ x 90 x 4
= 180

Remaining questions that each person has to answer
= 110 - 90
= 20

If Person K answers the last 20 questions correctly, the additional score that he will earn
= 20 x 4
= 80

Total score that Person K will earn after answering all the questions
= 180 + 80
= 260

Number of points that Person K is leading Person J by
= 260 - 252
= 8

For Person J to win the contest, the number of points he has to earn
= 8 + 4
= 12

Answer(s): 12