General Logical Reasoning and Puzzles 3 — Questions and Answers
Question 1: If no birds are reptiles, and all parrots are birds, which statement must be true?
- All reptiles are parrots
- No parrots are reptiles (Correct answer)
- Some parrots are reptiles
- All birds are parrots
Correct answer: No parrots are reptiles
Since all parrots are birds and no birds are reptiles, it follows necessarily that no parrots are reptiles.
Question 2: What is the missing term? ACE, BDF, CEG, ?
- DFH (Correct answer)
- EGI
- CFH
- DGI
Correct answer: DFH
Each triplet shifts every letter by +1: A→B→C→D, C→D→E→F, E→F→G→H, so the answer is DFH.
Question 3: Tom is older than Sam. Sam is older than Raj. Raj is older than Priya. Who is the youngest?
- Tom
- Sam
- Raj
- Priya (Correct answer)
Correct answer: Priya
The chain Tom > Sam > Raj > Priya places Priya at the bottom as youngest.
Question 4: A statement is made: 'If it rains, the ground is wet.' The ground is not wet. What can you conclude?
- It is raining
- It is not raining (Correct answer)
- It may or may not be raining
- The statement is false
Correct answer: It is not raining
By contrapositive, 'not wet ground' implies 'it did not rain.'
Question 5: Which figure completes the pattern? Each row contains a circle, triangle, and square. Row 3 has a circle and square. What is missing?
- Circle
- Square
- Triangle (Correct answer)
- Pentagon
Correct answer: Triangle
Each row must contain exactly one of each shape; the missing shape in row 3 is a triangle.
Question 6: A puzzle box has 3 dials each with digits 0–9. How many unique 3-digit combinations are possible (repetition allowed)?
- 100
- 720
- 1000 (Correct answer)
- 999
Correct answer: 1000
Each dial has 10 choices independently, so 10×10×10=1000 total combinations.
Question 7: Two candles of equal length are lit simultaneously. Candle A burns out in 3 hours; Candle B in 5 hours. After how many hours is Candle A half the length of Candle B?
- 1.5 hours
- 2.5 hours
- 1.875 hours (Correct answer)
- 2.0 hours
Correct answer: 1.875 hours
At time t: A=(1−t/3), B=(1−t/5); set A=B/2 → 1−t/3=(1−t/5)/2 → t=15/8=1.875 hours.
General Logical Reasoning and Puzzles 3
If no birds are reptiles, and all parrots are birds, which statement must be true?