A candidate just passed by getting 150 answers correct by attempting 225 of the total questions. Find the total number of questions in the examination if a candidate needs 60% marks.(All questions carry equal marks)
Let the total number of questions be x. then, Percentage need in exam = 60% Correct answer = 150 percentage = (correct answer)/(total questions) 
100 60 = (150/x) × 100 x = 250 Alternate method Given that 150 ≡ 60% 1 ≡ 10/25 % 250 ≡ 100% Total number of questions = 250
40 42 87 266 ? 5366
22, 23, 31, 57, 122, 247
32, 65 , 196, 785, ? , 23557
19.11 × 5.98 + 20.03 × 3.12 – 34.95 + 97.9 × 3.02 =?
7200 7200 3600 1200 300 ?
...0.5 1.5 5 ? 76 385
...24, 33, 50, ?, 108, 149
25, 200, 40, ?, 64, 512
1400 350 700 175 ? 87.5
...7 12 33 ? 635 3804
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