Each of C, D, E, F, X, Y and Z has an exam on a different day of a week starting from Monday and ending on Sunday of the same week.
No one has exam before Z. Only three people have exam between Z and F. Only one person has exam between F and X. Y has exam on Wednesday. D has exam on one of the days after E but on one of the days before C. On which day of the week does D have exam?3867

Correct Answer: Thursday

Step-by-Step Explanation:

Let us arrange the 7 persons (C, D, E, F, X, Y, Z) across the 7 days of the week, starting from Monday and ending on Sunday.

Step 1: Determine the fixed positions given directly in the clues.

1. "No one has exam before Z."
This means Z must have the exam on the very first day of the week, which is Monday.
• Monday: Z

2. "Y has exam on Wednesday."
This directly fixes Y on Wednesday.
• Wednesday: Y

Step 2: Determine the positions of F and X.

3. "Only three people have exam between Z and F."
Since Z is on Monday (Day 1), skipping 3 days (Tuesday, Wednesday, Thursday) places F on the 5th day, which is Friday.
• Friday: F

4. "Only one person has exam between F and X."
F is on Friday. The person one day away could be Wednesday or Sunday. Since Wednesday is already occupied by Y, X must have the exam on Sunday.
• Sunday: X

Step 3: Determine the positions of E, D, and C.

So far, we have filled:
• Monday: Z
• Wednesday: Y
• Friday: F
• Sunday: X

The remaining vacant days are:
• Tuesday
• Thursday
• Saturday

5. "D has exam on one of the days after E but on one of the days before C."
This gives the relative order: E ... D ... C.
Placing E, D, and C in order into the remaining days (Tuesday, Thursday, Saturday):
• Tuesday: E
• Thursday: D
• Saturday: C

Final Schedule:
• Monday: Z
• Tuesday: E
• Wednesday: Y
• Thursday: D
• Friday: F
• Saturday: C
• Sunday: X

Therefore, D has the exam on Thursday.