What is the sum of the one who lives in floor 1 and the one who is to the immediate left of R?
- AOption (a)
17
- BOption (b)
18
- COption (c)
21
- DOption (d)
20
- EOption (e)
19
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Correct answer
21
Why this answer is correct
There is a building in which total of ten rooms are present in which odd numbered floor has one room and even numbered floor have two rooms.
| Floors | Rooms | |
|---|---|---|
| 7 | ||
| 6 | ||
| 5 | ||
| 4 | ||
| 3 | ||
| 2 | ||
| 1 |
Arrangement 1:
(6,5), (1,1), (6,3), (3,5), (2,3), (4,3), (1,4), (3,4), (4,2), (1,2).
The operation will be carried out from left to right on this above output.
1. First fill one room on each even numbered floor in decreasing order of the floor. i.e., numbers are filled in order of floor 6, floor 4 and floor 2. 2. For even numbered floor the digits in the output will be added.
On taking the first three outputs and adding the digits we get,
(6,5) 6+5=11 in floor 6.
(1,1) 1+1=2 in floor 4.
(6,3) 6+3=9 in floor 2.
| Floors | Rooms | |
|---|---|---|
| 7 | ||
| 6 | 11 | |
| 5 | ||
| 4 | 2 | |
| 3 | ||
| 2 | 9 | |
| 1 |
3. Then fill the odd numbered floor in increasing order. i.e., order of filling is floor 1, floor 3, floor 5 and floor 7. 4. For odd numbered floor the digits in the output will be multiplied.
On taking the next four outputs and multiplying them, we get
(3,5) 3x5=15 in floor 1.
(2,3) 2x3=6 in floor 3.
(4,3) 4x3=12 in floor 5.
(1,4) 1x4=4 in floor 7.
| Floors | Rooms | |
|---|---|---|
| 7 | 4 | |
| 6 | 11 | |
| 5 | 12 | |
| 4 | 2 | |
| 3 | 6 | |
| 2 | 9 | |
| 1 | 15 |
5. The remaining will be filled in decreasing order of even numbered floor. i.e., filled in order of floor 6, floor 4 and floor 2.
(3,4) 3+4=7 in floor 6.
(4,4) 4+4=8 in floor 4.
(1,2) 1+2=3 in floor 2.
| Floors | Rooms | |
|---|---|---|
| 7 | 4 | |
| 6 | 11 | 7 |
| 5 | 12 | |
| 4 | 2 | 8 |
| 3 | 6 | |
| 2 | 9 | 3 |
| 1 | 15 |
Arrangement 2:
E, V, I, F, A, H, R, M, T, P.
Vowels: A, E, I.
Alphabets before letter L: F, H.
Alphabets after letter L: M, P, R, T, V
6. All the vowels will be placed with the odd prime numbers in decreasing order of the number and the increasing alphabet order of the vowels according to the English alphabet.
Decreasing order of odd prime numbers in rooms: 11, 7, 3.
Increasing order of vowels: A, E, I.
11 - A
7 - E
3 - I.
| Floors | Rooms | |
|---|---|---|
| 7 | 4 | |
| 6 | 11 - A | 7 - E |
| 5 | 12 | |
| 4 | 2 | 8 |
| 3 | 6 | |
| 2 | 9 | 3 - I |
| 1 | 15 |
7. The alphabets before the letter L according to English alphabet will be placed with the square numbers in increasing order of the number and increasing order of the letters according to the English alphabets.
Increasing order of square numbers in rooms: 4, 9.
Increasing order of letters before L: F, H.
4 - F
9 - H.
| Floors | Rooms | |
|---|---|---|
| 7 | 4 - F | |
| 6 | 11 - A | 7 - E |
| 5 | 12 | |
| 4 | 2 | 8 |
| 3 | 6 | |
| 2 | 9 - H | 3 - I |
| 1 | 15 |
8. The remaining letters will be allotted in the increasing order of the remaining numbers and the increasing order of the remaining letters according to the English alphabet.
Increasing order of the remaining numbers: 2, 6, 8, 12 and 15.
Increasing order of the remaining letters: M, P, R, T and V.
2 - M
6 - P
8 - R
12 - T
15 - V.
| Floors | Rooms | |
|---|---|---|
| 7 | 4 - F | |
| 6 | 11 - A | 7 - E |
| 5 | 12 - T | |
| 4 | 2 - M | 8 - R |
| 3 | 6 - P | |
| 2 | 9 - H | 3 - I |
| 1 | 15 - V |
Arrangement 3:
The letters are then placed in the linear seating arrangement in which all are facing the north direction.
9. The number of letters between I and A is equal to the number of persons between I and E. 10. No vowel sits at the end of the line. The number of letters between I and E is an even prime number. i.e., 2.
11. Three persons sit between I and the one who lives in first floor. i.e., V. 12. M sits to the immediate right of V.
13. R sits fourth to the left of E. So, case 1 is eliminated. 14. H sits at one of the end of the line. 15. The one whose room is in 5th floor (T) sits to the immediate right of the one who has an even square number. i.e., 4 (F).
The final arrangement is,
Thus, the sum of the one who lives in floor 1 i.e., V (15) and the one who is to the immediate left of R i.e., P(6) is 15+6=21.
Thus, 21 is the answer.

