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Practice Exams

Logical Reasoning Reviewer (Professional)

Reviewer's Note: Don't overthink! In Syllogisms, stick strictly to the premises provided. Even if a premise says "all cats are birds," accept it as truth for the duration of that question.

Logical Reasoning tests your ability to think clearly and systematically.

Sa madaling salita: Ito ay pag-test sa iyong logic. Kailangan mong sumunod sa "rules" ng logic kahit mukhang mali ito sa totoong buhay.

1. Syllogisms

Consists of two premises and a conclusion. Determine if the conclusion is valid.

  • Premise 1: All dogs are mammals.
  • Premise 2: Fido is a dog.
  • Conclusion: Fido is a mammal. (Valid)
  • Rationale: Kung ang lahat ng A ay B, at ang C ay isang A, ibig sabihin ang C ay B din.

Tips for Syllogisms:

  • Draw Venn Diagrams: Ito ang pinakamadaling paraan para ma-visualize ang logic.
  • Avoid Bias: Huwag gamitin ang "common sense" kung labas ito sa sinasabi ng premises.

2. Logic Puzzles (Seating/Ordering)

Arranging people or objects based on rules.

  • Strategy: Draw a diagram. (Gumuhit ng row o circle para hindi malito.)
  • Rationale: Ilagay muna ang mga taong may "fixed" na posisyon.

3. Letter and Number Logic

Identifying patterns in sequences.

  • Example: A, C, E, G, ? (Answer: I - laktaw ng isa.)
  • Example: Z1, Y2, X3, ? (Answer: W4 - pabaliktad ang alphabet, pataas ang numero.)

4. Inductive vs. Deductive

Reasoning can flow from the general to the specific or vice versa.

  • Deductive: From General rule to Specific case. (Malaki papunta sa maliit.)
  • Inductive: From Specific cases to General rule. (Maliit papunta sa malaki.)

5. Common Logic Traps

  • All vs. some: If a statement says "some," do not upgrade it to "all."
  • Not all: This means at least one exception exists.
  • Either/or: The correct answer may depend on the nearest subject or the exact wording.
  • Hidden assumptions: Do not bring in outside facts, even if they seem obvious.
  • Sequence errors: In ordering questions, check every rule before locking your answer.

6. Syllogism Shortcuts

  • If all A are B and all B are C, then all A are C.
  • If some A are B, that does not mean all A are B.
  • If no A are B, then A and B never overlap.
  • If some A are not B, only part of the group is excluded.

7. Ordering Puzzle Method

When solving seat, race, or ranking items:

  • Draw the line, row, or circle first.
  • Put fixed positions in place.
  • Add the strongest clues next.
  • Test the remaining spaces one by one.

Mini Guide

Clue Type What It Tells You
Before Earlier position
After Later position
Between Middle position
Immediately before Adjacent earlier position
Immediately after Adjacent later position

8. Pattern Recognition Tips

  • Watch for alternating letters.
  • Watch for plus or minus changes in numbers.
  • Check whether the rule repeats every two or three steps.
  • Verify if the pattern changes both symbol and quantity.

Practice Questions

  1. Premise 1: All scientists are thinkers. Premise 2: Some thinkers are inventors. Conclusion: Therefore, all scientists are inventors.

    • A. Valid
    • B. Invalid
    • Answer: B (Invalid).
    • Rationale: Dahil "some" lang ang thinkers na inventors, hindi sigurado kung kasama doon ang mga scientists. Kung saan, hindi valid ang conclusion.

  2. Race Order: Alan finished before Ben but after Carl. Carl finished after Dan. Ed was last. Who won?

    • A. Alan
    • B. Carl
    • C. Dan
    • Analysis: Dan →\to Carl →\to Alan →\to Ben →\to Ed.
    • Answer: C (Dan).
    • Rationale: Ito ay halimbawa ng ordering puzzle. Mas madali kung gagawa ka ng timeline.

  3. Pattern: B2, D4, F6, H8, ?

    • A. J10
    • B. I9
    • Answer: A (J10).
    • Rationale: Ang letters ay lumalaktaw (B, [C], D, [E], F...). Ang numbers ay +2+2.

  4. Syllogism: All teachers are readers. Some readers are writers. Therefore, some teachers are writers.

    • A. Valid
    • B. Invalid
    • Answer: B (Invalid).
    • Rationale: "Some readers" does not prove that the teachers are included.

  5. Ordering: A is older than B, B is older than C, and C is older than D. Who is the youngest?

    • A. A
    • B. B
    • C. C
    • D. D
    • Answer: D (D).
    • Rationale: The youngest is the one at the end of the chain.

  6. Pattern: 2, 4, 8, 16, ?

    • A. 18
    • B. 24
    • C. 32
    • D. 36
    • Answer: C (32).
    • Rationale: Doubles each time.

Tip: Logic is like a muscle. Practice daily! (Ang logic ay parang muscle, kailangang i-exercise araw-araw.)