Question
A candidate just passed by getting 15 answers correct by
attempting 25 of the total questions. Find the total number of questions in the examination if a candidate needs 60% marks. (All questions carry equal marks)Solution
Let the total number of questions be x. then, Percentage need in exam = 60% marks obtained = 15 percentage = (marks obtained)/(total marks) 
100 60 = 100 x = 25 Alternate method Given that 15 ≡ 60% 1 ≡ 4% 25 ≡ 100% total number of questions = 25
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