Question
How many files are facing the north direction?
Study the following information carefully and answer the questions given below. Nine files viz. M, N, O, P, Q, R, S, T and U are placed in a straight line on the table, but not necessarily in the same order. Some of them are facing north while some are facing south and not more than two adjacent files are facing the same direction. The consecutive alphabetically named files are not adjacent to each other. O is placed at one of the ends and is facing towards the north. Q is placed three files away from O and faces the same direction as O. P is placed sixth to the right of S and vice versa where none of them are placed at the ends. Only two files are placed between P and T, which faces the same direction as P. U is placed second to the left of R whereas N is placed second to the right of Q. Both M and N face the same direction.Solution
O is placed at one of the ends and is facing towards the north. Q is placed three files away from O and faces the same direction as O. Case-1 
Case-2 
U is placed second to the left of R whereas N is placed second to the right of Q. Both M and N face the same direction. Not more than two adjacent files are facing the same direction. Hence, case 2 gets eliminated. 
What will come in place of the question mark (?) in the following series?
18, 26, 37, 51, ?, 88
14, 20, ?, 50, 74, 104
What will come in place of the question mark (?) in the following series?
55,...
What will come in the place of questions (?) mark in the following questions.
1279, 1265, ? , 1225, 1193, 1149
728, 737, ?, 778, 814, 863Â
?, 15, 45, 225, 1575, 14175
84, 105, ?, 168, 210, 259
9 28 83 250 ? 2248
3, 8, 27, 124, ?
What value should come in the place of (?) in the following number series?
180, 194, ?, 264, 320, 390
