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
147 490 707 831 895 922 930
...Find the wrong number in the given number series.
24, 120, 720, 5040, 40320, 362881
134, 138, 132, 142, 126, 146, 122
Find the wrong number in the given number series.
45,  54, 79, 128, 189,  330,  499
Find the wrong number in the given number series.
148, 146, 140, 128, 108, 68
547, 594, 640, 691, 741, 792
Find the wrong number in the following series.
30, 36, 42, 52, 59, 68
1137, 1138, 1142, 1151, 1185, 1310Â
100, 125, 143, 169, 198, 230, 265
97, 98, 107, 132, 181, 264