Directions (71-75) : Study the following information carefully and answer the question given below:

Seven persons sit in a row facing to the south and they all have different ages. E sits 2nd from one of the extreme ends. Three persons sit between E and the one who is 25 years old. The one who is 25 years old is the only neighbour of A. D sits to the right of C. The Age of D is equal to the total age of his immediate neighbours. C is 15 years old and sits 3 rd to the right of E. B is 10 years older than A and 10 years younger than G who sits at one of the extreme ends. F sits to the right of B who is 1 year younger than E whose age is thrice of age of F.

Four of the following five are alike in a certain way and so form a group. Find the one who does not belong to that group?

The correct option is A.

Step-by-step Explanation:

1. Understanding the Directions and Arrangement:

There are seven persons facing South. Facing South means:

• Right side is towards the West (left side from our perspective looking at the paper).

• Left side is towards the East (right side from our perspective looking at the paper).

Let the 7 positions in the row from left to right (facing South) be position 1 to position 7 (where position 1 is the West/Right end and position 7 is the East/Left end):

• E sits 2nd from one of the extreme ends.

• Three persons sit between E and the one who is 25 years old.

• The one who is 25 years old is the only neighbour of A. This implies A must be at an extreme end, and the 25-year-old is at the 2nd position from that end.

• C is 15 years old and sits 3rd to the right of E (towards the West end).

Since C sits 3rd to the right of E, E cannot be near the West end. Therefore, E must sit 2nd from the East end (position 6 from West, or position 2 from East).

Let's map positions from Left (West end) to Right (East end):

• Position 6: E

• C sits 3rd to the right of E (facing South, right is towards position 1). So C is at Position 3 (6 - 3 = 3). C = 15 years old.

• Three persons sit between E (Position 6) and the one who is 25 years old. So the 25-year-old is at Position 2.

• The one who is 25 years old is the only neighbour of A, which means A is at Position 1 (the extreme West end).

Now, let's place G:

• G sits at one of the extreme ends. Since Position 1 is occupied by A, G must sit at Position 7 (the extreme East end).

Now we have persons at positions:

1: A

2: (25 years old)

3: C (15 years old)

4: ?

5: ?

6: E

7: G

Remaining persons to place: D, B, F.

• F sits to the right of B. Since they face South, "to the right" means towards a lower position number.

• D sits to the right of C (towards position 1 or 2). Position 1 is A, so D must be at Position 2!

Thus:

Position 2: D (25 years old)

The remaining positions 4 and 5 must be filled by B and F.

Since F sits to the right of B, F must be at Position 4 and B must be at Position 5.

So the complete linear seating arrangement from position 1 to 7 is:

Position 1: A

Position 2: D (25 years old)

Position 3: C (15 years old)

Position 4: F

Position 5: B

Position 6: E

Position 7: G

2. Evaluating the Odd One Out:

Let's analyze the positions of the persons listed in the options:

• D: Position 2 (Intermediate position / has two neighbours)

• F: Position 4 (Intermediate position / has two neighbours)

• C: Position 3 (Intermediate position / has two neighbours)

• E: Position 6 (Intermediate position / has two neighbours)

• A: Position 1 (Extreme end of the row / has only one neighbour)

Clearly, A is the only person sitting at an extreme end of the row, whereas D, F, C, and E are all sitting in intermediate positions. Thus, A does not belong to the group.