M has an exam on Thursday. Exactly 4 people have their exams between O and A, neither of whom has an exam on Sunday. Q has an exam immediately before C. I does not have an exam on Friday. O does not have an exam after C.
How many people have exams after A?
The problem requires determining the number of people scheduled for exams after person A, given specific constraints for seven individuals (A, C, I, M, O, Q, W) across a Monday-to-Sunday week.
The constraint of exactly 4 people between O and A implies their exams must be scheduled 5 days apart. In a 7-day week (Monday to Sunday), the only pair of days 5 days apart is Monday and Saturday. This pairing respects the constraint that neither O nor A can be on Sunday.
Thus, the set of exam days for {O, A} must be {Monday, Saturday}.
M's exam is fixed on Thursday.
The constraints 'O before C' and 'Q immediately before C' dictate that the QC block must occur sometime after O.
We examine two possible scenarios for the {O, A} placement:
The initial schedule framework is:
The QC block needs to fit after O (Monday). Potential slots are (Tue, Wed), (Wed, Thu), or (Thu, Fri). Since M is scheduled on Thursday, the slots (Wed, Thu) and (Thu, Fri) are unavailable for QC.
Therefore, the QC block must occupy Tuesday and Wednesday.
The schedule progresses to: O, Q, C, M, ?, A, ?
The remaining people are I and W, and the remaining days are Friday and Sunday.
According to Constraint 5, I cannot have an exam on Friday. This forces I to be scheduled on Sunday, leaving Friday for W.
This scenario results in the following complete schedule:
| Day | Mon | Tue | Wed | Thu | Fri | Sat | Sun |
| Person | O | Q | C | M | W | A | I |
This arrangement satisfies all the given conditions.
The initial schedule framework is:
Constraint 'O before C' requires C's exam to be after O (Saturday). The only available day is Sunday.
The schedule becomes: A, ?, ?, M, ?, O, C
Constraint 'Q immediately before C' implies Q must take the slot immediately preceding Sunday, which is Saturday. However, O is already scheduled for Saturday.
This conflict means Case 2 is not possible.
The only valid exam schedule determined from the constraints is:
A's exam is scheduled for Saturday. The question asks for the number of people with exams scheduled *after* A.
Only person I has an exam on Sunday, which occurs after Saturday.
Therefore, exactly 1 person has an exam after A.
Seven friends O, P, Q, R, S, T and U are watching a movie sitting in a row. S is sitting at one extreme end. P is sitting second to the right of S. P is sitting between O and Q. U is NOT sitting at any extreme end. R Is sitting to the immediate left of T. Q does not sit beside S.Who is sitting at the extreme left end?
What should come in place of the question mark (?) in the given series?
86, 88, 90, 92, 94, ?
G, H, J, K, L and P live on six different floors of the same building. The lowest floor in the building is numbered 1, the floor above it, number 2 and so on till the topmost floor is numbered 6. Only two people live between P and K. Only two people live between P and H. No one lives above P. K lives below H, but above L. How many people live below G?
Seven students, Q, R, S, T, W, X and Y, are sitting in a straight line facing north. Only two people sit to the right of W. Only two people sit between W and X. Only two people sit between Y and R. R sits to the immediate left of W. S sits to the immediate right of Q. How many people sit between S and T?
R, A, D, I, U and S live on six different floors of the same building. The lowermost floor in the building is numbered 1, the floor above it, number 2 and so on, till the topmost floor is numbered 6. Only two people live between I and U. Only A lives above R. D lives on an even numbered floor. I lives on the lowermost floor. How many people live between S and A?