Question
A candidate just passed by getting 50 answers correct by
attempting 75 of the total questions. Find the total number of questions in the examination if a candidate needs 50% marks. (All questions carry equal marks)Solution
Let the total number of questions be x. then, Percentage need in exam = 25% Correct answer = 50 percentage = (correct answer)/(total questions) 
100 25 = 100 x = 200 Alternate method Given that 50 ≡ 25% 1 ≡ % 200 ≡ 100% total number of questions = 200
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