Part III — Reasoning Ability: Logical & Analytical Reasoning

Chapter 3: Blood Relations, Coding, Syllogism & Inequalities

3.1 Blood Relations and Direction Sense

Blood relation problems trace family relationships through a chain of statements, best solved via a family-tree diagram distinguishing generations and gender. Direction sense problems track movement in various directions (typically from a reference point, facing north) to determine final position or distance, best solved by plotting on a coordinate grid using the Pythagorean theorem for diagonal distances.

3.2 Coding-Decoding

Coding-decoding questions establish a letter/number substitution pattern from a given example (e.g., a consistent forward or backward shift, or a more complex substitution rule), applied consistently to derive a new word's code or decode a coded word.

3.3 Syllogism

Syllogisms test logical deduction from categorical statements ("All A are B," "Some A are B," "No A are B," "Some A are not B"), best verified using Venn diagrams to check whether a proposed conclusion follows necessarily from the given premises under every possible diagram consistent with them.

3.4 Inequality and Alphanumeric Series

Inequality reasoning (e.g., "A > B ≥ C > D") requires combining relational statements logically to determine which conclusions necessarily follow in every case. Alphanumeric series questions mix letters, numbers, and symbols in a sequence, requiring identification of a repeating or evolving pattern.

3.5 Data Sufficiency

Data Sufficiency questions present a question along with two or more numbered statements, requiring the candidate to determine whether each statement alone, or both together, is sufficient to answer the question — without necessarily solving it fully.

3.6 Practice Set — Logical & Analytical Reasoning (20 MCQs)

1. Pointing to a photograph, a man says, "She is my mother's only daughter's daughter." How is the girl related to the man?
   (a) Sister (b) Niece (c) Daughter (d) Cousin
2. If A is B's father, B is C's mother, and C is D's brother, then A is D's:
   (a) Grandfather (b) Uncle (c) Father (d) Brother
3. A woman walks 9 km north, then turns right and walks 12 km. How far is she from her starting point?
   (a) 13 km (b) 15 km (c) 17 km (d) 21 km
4. A man walks 5 km east, then turns left and walks 5 km, then turns left again and walks 5 km. How far is he from his starting point, and in which direction?
   (a) 5 km, north of the starting point (b) 10 km, east of the starting point (c) 5 km, east of the starting point (d) 15 km, north of the starting point
5. If in a code, POLICY is written as QPMJDZ (each letter shifted forward by 1), how is INSURANCE written?
   (a) JOTVSBODF (b) JOTVSBODE (c) JPTVSBODF (d) JOTVTBODF
6. If in a code, MANAGE is written as 13-1-14-1-7-5 (letter positions), how would ADMIN be written?
   (a) 1-4-13-9-14 (b) 1-4-13-9-13 (c) 1-4-14-9-14 (d) 1-5-13-9-14
7. Given: "All employees are professionals. Some professionals are managers." Which conclusion necessarily follows?
   (a) All employees are managers (b) Some professionals are employees (c) No definite conclusion about employees being managers can be drawn from these two statements alone (d) No employees are professionals
8. Given: "No insurers are brokers. All brokers are agents." Which conclusion necessarily follows?
   (a) No insurers are agents (b) Some agents are not insurers, specifically the brokers (c) All insurers are agents (d) All agents are brokers
9. Given: P > Q ≥ R > S ≥ T. Which of the following must be true?
   (a) P > T (b) T > P (c) Q < T (d) R > P
10. Given: X ≥ Y > Z and Z ≥ W. Which of the following must be true?
    (a) X > W (b) W > X (c) Y < W (d) Z > X
11. In the alphanumeric series A1, C3, E5, G7, ?, what is the next term (odd-position letters skipping one, odd numbers)?
    (a) I9 (b) H8 (c) I8 (d) H9
12. Data Sufficiency: "What is the value of x?" Statement I: x + 5 = 12. Statement II: x is a positive integer. Which is sufficient?
    (a) Statement I alone is sufficient, Statement II alone is not (b) Statement II alone is sufficient, Statement I alone is not (c) Both statements together are necessary (d) Neither statement is sufficient even together
13. Data Sufficiency questions primarily test whether:
    (a) The given data is grammatically correct (b) The given data is sufficient to answer a question (c) The question has no answer (d) Only calculation speed
14. In the letter series Z, W, T, Q, ?, what is the next letter (gaps -3 each time)?
    (a) M (b) N (c) O (d) P
15. Venn diagrams are particularly useful for solving:
    (a) Only numerical simplification (b) Syllogism-type logical deduction problems (c) Only direction sense problems (d) Only coding-decoding problems
16. If "P # Q" means "P is the father of Q," "P @ Q" means "P is the mother of Q," and "P & Q" means "P is the sibling of Q," what does "A # B & C" establish about A and C?
    (a) A is C's father, since A is B's father and B is C's sibling (b) A is C's sibling (c) A is C's mother (d) No relationship can be established
17. Inequality reasoning conclusions are considered valid only if they:
    (a) Necessarily follow from the given statements under all interpretations (b) Are merely plausible (c) Contradict the given statements (d) Require additional unstated assumptions
18. In the number-letter series 2A, 4C, 6E, 8G, ?, what is the next term (even numbers, alternating letters)?
    (a) 10I (b) 9H (c) 10H (d) 9I
19. A blood relation puzzle states: "R is S's son. S is T's daughter. T is U's wife." How is R related to U?
    (a) R is U's grandson (assuming U is male) or grandchild (b) R is U's son (c) R is U's brother (d) Cannot be determined without knowing U's gender, though the generational relationship (grandchild) is clear
20. Coding-decoding questions are best approached by:
    (a) Memorising every possible code in advance (b) Establishing the substitution pattern from the given example and applying it consistently (c) Guessing based on word length alone (d) Ignoring the given example

Answer Key

1.(c)

2.(a)

3.(b)

4.(a)

5.(a)

6.(a)

7.(c)

8.(a)

9.(a)

10.(a)

11.(a)

12.(a)

13.(b)

14.(b)

15.(b)

16.(a)

17.(a)

18.(a)

19.(d) 20.(b)