Read the following information carefully and answer the questions given below:

Eight persons — A, B, C, D, E, F, G and H — were born on two different dates i.e. 11th and 20th of four different months viz. August, October, November and December of the same year. No two persons were born on the same day.

G was born four persons before B. B was born in the month having even number of days. E was born two persons after G. A was born three persons before E. F was born in the month having even number of days. F was born after C. D was born on an odd number date.

Four of the following five are alike in a certain way and thus form a group. Find the one who doesn’t belong to the group?

` tag: detailed step-by-step logic. Let's output the result carefully. B

The correct answer is B.

Step-by-Step Explanation:

Let's first determine the exact birth order of all eight persons based on the given conditions.

The given months and dates in chronological order are:

1. August 11th (31 days)

2. August 20th (31 days)

3. October 11th (31 days)

4. October 20th (31 days)

5. November 11th (30 days - even number of days)

6. November 20th (30 days - even number of days)

7. December 11th (31 days)

8. December 20th (31 days)

Step 1: Determine the positions of B, G, E, and A

• "B was born in the month having even number of days."
The month with an even number of days is November (30 days). Thus, B is born on either 11th November (Position 5) or 20th November (Position 6).

• "G was born four persons before B."
This means Position(G) = Position(B) - 4.

• "E was born two persons after G."
This means Position(E) = Position(G) + 2.

• "A was born three persons before E."
This means Position(A) = Position(E) - 3.

Let's test both possible positions for B:

• Case 1: If B is born on 11th November (Position 5):
Position of G = 5 - 4 = Position 1 (11th August)
Position of E = 1 + 2 = Position 3 (11th October)
Position of A = 3 - 3 = 0 (Invalid, as positions start from 1).

• Case 2: If B is born on 20th November (Position 6):
Position of G = 6 - 4 = Position 2 (20th August)
Position of E = 2 + 2 = Position 4 (20th October)
Position of A = 4 - 3 = Position 1 (11th August)

Case 2 is valid. Therefore, the positions so far are:

• Position 1 (11th Aug): A

• Position 2 (20th Aug): G

• Position 4 (20th Oct): E

• Position 6 (20th Nov): B

Step 2: Place F and C

• "F was born in the month having even number of days."
November is the only month with an even number of days (30 days). Since Position 6 is occupied by B, F must be born on 11th November (Position 5).

• "F was born after C."
Since F is at Position 5, C must be born before Position 5. The only remaining empty slot before Position 5 is Position 3 (11th October). So, C is born on 11th October.

Step 3: Place D and H

• "D was born on an odd number date."
The remaining slots are Position 7 (11th Dec) and Position 8 (20th Dec). Since 11 is an odd number, D is born on 11th December (Position 7).

• The only remaining person, H, is born on 20th December (Position 8).

Final Arrangement:

11th August: A

20th August: G

11th October: C

20th October: E

11th November: F

20th November: B

11th December: D

20th December: H

Finding the odd one out:

• E was born in October (31 days).

• C was born in October (31 days).

• G was born in August (31 days).

• B was born in November (30 days).

All persons except B were born in months having 31 days (an odd number of days), whereas B was born in a month having 30 days (an even number of days). Hence, B does not belong to the group.