Directions (77-81): Read the following information carefully and answer the questions given below:

Ten persons- M, N, O, P, Q, R, S, T, U and V live on different floors of a ten-storey building where ground floor is numbered as 1, above it is 2 and so on till the topmost floor is numbered as 10.

Four persons live between N and O who lives immediate below P. N lives on an even numbered floor but not on top floor. Q lives three floors below P. The number of persons live above R is same as the number of persons live below S but they do not live adjacent to each other. T lives adjacent to S. U lives on an odd numbered floor but above V and below M.

Who among the following lives just above the floor on which N lives?

The correct answer is U.

Let's carefully decode all the clues step-by-step to build the complete floor arrangement.

Step 1 – Identify the N–O–P–Q block

The clues tell us:

• Four persons live between N and O → |Floor(N) − Floor(O)| = 5
• O lives immediately below P → Floor(P) = Floor(O) + 1
• N lives on an even numbered floor, but not floor 10
• Q lives three floors below P → Floor(Q) = Floor(P) − 3

Testing N = 4 with O above N:

Floor(O) = 4 + 5 = 9, Floor(P) = 9 + 1 = 10, Floor(Q) = 10 − 3 = 7

This is valid (N=4 is even and not 10). ✓

Step 2 – Remaining floors and the R–S condition

Floors used so far: N=4, O=9, P=10, Q=7
Remaining floors for M, R, S, T, U, V: 1, 2, 3, 5, 6, 8

The clue states: number of persons above R = number of persons below S

• Persons above R on floor r = 10 − r
• Persons below S on floor s = s − 1

Setting them equal: 10 − r = s − 1 → r + s = 11

From the available floors {1, 2, 3, 5, 6, 8}, the pair that sums to 11 and is not adjacent (|r − s| ≠ 1):

→ R = 8, S = 3 (|8 − 3| = 5, not adjacent ✓)

Step 3 – Place T (adjacent to S)

T must be on floor 2 or 4. Floor 4 is taken by N, so T = 2. ✓

Step 4 – Place M, U, V (remaining floors: 1, 5, 6)

Clue: U is on an odd floor, with V below U and M above U.

From {1, 5, 6}, the only odd floor is 5 and 1.

• If U = 1: no floor below 1 for V → impossible.
• If U = 5: V must be below 5 → V = 1; M must be above 5 → M = 6. ✓

Step 5 – Complete Floor Arrangement

Step 6 – Verification of all clues

✅ Four persons (U, M, Q, R on floors 5–8) between N(4) and O(9)
✅ O(9) is immediately below P(10)
✅ N is on floor 4 — even and not floor 10
✅ Q(7) is three floors below P(10)
✅ Persons above R(8) = 2; Persons below S(3) = 2 → equal ���; |8−3|=5, not adjacent ✓
✅ T(2) is adjacent to S(3)
✅ U(5) is on an odd floor; V(1) < U(5) < M(6)

Answer: N lives on floor 4. The floor immediately above floor 4 is floor 5, which is occupied by U.