Directions (81-85): Study the following information carefully and answer the questions given below:

Eight persons buy different things one after other. Two persons buy between M and L who buys immediately before Q. O buys two persons before Q. As many persons buy between O and Q as between L and K. K buys before O. Two persons buy between K and P. J buys before N and after P.

If all the persons buy things in the alphabetical order from bottom to top then the position of how many persons remains unchanged?

Correct Answer: One

Let us determine the buying sequence of the eight persons (J, K, L, M, N, O, P, Q) step-by-step from top (1st) to bottom (8th):

1. Analyze the positions of O, L, and Q:
- "L buys immediately before Q" means we have the pair: L, Q.
- "O buys two persons before Q" means there is exactly one person between O and Q (O _ Q). Since L is immediately before Q, the sequence must be: O, L, Q.

2. Determine the position of K:
- "As many persons buy between O and Q as between L and K."
- Between O and Q, there is 1 person (L). Hence, there must be exactly 1 person between L and K.
- "K buys before O" means K is placed before O. Therefore, the sequence becomes: K, O, L, Q.

3. Find the position of P:
- "Two persons buy between K and P."
- Since K is followed immediately by O and L, P cannot be after K. Thus, P must be placed before K, leaving two positions between them: P, _, _, K, O, L, Q.

4. Incorporate M, J, and N:
- "Two persons buy between M and L."
- Since the sequence containing L is P, _, _, K, O, L, Q, the two persons between M and L must be K and O. This places M at the third position: P, _, M, K, O, L, Q, _.
- "J buys before N and after P."
- Since P is at the first position, J and N must occupy the remaining empty positions (2nd and 8th). Since J buys before N, J is at the 2nd position and N is at the 8th position.

The final buying order from top (1st) to bottom (8th) is:
1. P
2. J
3. M
4. K
5. O
6. L
7. Q
8. N

5. Rearrange in alphabetical order from bottom to top:
The alphabetical order of the eight persons is J, K, L, M, N, O, P, Q. Arranging them from bottom (8th) to top (1st):
1. Q
2. P
3. O
4. N
5. M
6. L
7. K
8. J

6. Compare the original and new positions:
- Position 1: P → Q (Changed)
- Position 2: J → P (Changed)
- Position 3: M → O (Changed)
- Position 4: K → N (Changed)
- Position 5: O → M (Changed)
- Position 6: L → L (Unchanged)
- Position 7: Q → K (Changed)
- Position 8: N → J (Changed)

Thus, the position of only one person (L) remains unchanged.