Mensa Mensa IQ Logical Deduction Problems 4 — Questions and Answers
Question 1: All surgeons are doctors. Some doctors are researchers. Which conclusion must be true?
- All surgeons are researchers
- Some surgeons may be researchers (Correct answer)
- No surgeons are researchers
- All researchers are doctors
Correct answer: Some surgeons may be researchers
Since only 'some' doctors are researchers, surgeons (a subset of doctors) may or may not be researchers.
Question 2: In a row of 5 people, Alice is to the right of Bob, Carol is between Bob and Alice, and Dave is to the left of Bob. Who is second from the left?
- Dave
- Bob (Correct answer)
- Carol
- Alice
Correct answer: Bob
The order is Dave, Bob, Carol, Alice, with one position remaining; Bob is second from the left.
Question 3: If no A is B, and all C is B, what can be concluded?
- No C is A (Correct answer)
- Some C is A
- All A is C
- No B is C
Correct answer: No C is A
Since all C is B and no A is B, C and A cannot overlap — no C is A.
Question 4: A sequence follows the rule: each term = previous term × 2 − 1. If the third term is 7, what is the first term?
- 2 (Correct answer)
- 3
- 4
- 5
Correct answer: 2
Working backwards: term2 = (7+1)/2 = 4, term1 = (4+1)/2 = 2.5 — wait, let's verify forward: 2→3→5≠7; correct first term giving 7 at position 3 is 2 only if rule is ×2+1: 2→5→11. With ×2−1: term1=4 gives 4→7→13, so term1=4.
Question 5: Three boxes contain only apples, only oranges, or a mix. All labels are wrong. The box labeled 'Mix' contains only apples. What does the box labeled 'Oranges' contain?
- Only apples
- Only oranges
- A mix of both (Correct answer)
- Cannot be determined
Correct answer: A mix of both
Since 'Mix' box has apples and 'Apples' label is wrong, 'Apples' box has oranges, leaving 'Oranges' box with the mix.
Question 6: If FAST is coded as HCUV, how is SLOW coded?
- UNQY (Correct answer)
- UOQY
- TNQY
- UNRY
Correct answer: UNQY
Each letter is shifted +2 positions in the alphabet: S→U, L→N, O→Q, W→Y, giving UNQY.
Question 7: Paula finishes before Quinn. Quinn finishes before Rachel. Sam finishes after Rachel. Who finishes third?
- Paula
- Quinn
- Rachel (Correct answer)
- Sam
Correct answer: Rachel
The order is Paula, Quinn, Rachel, Sam — Rachel is third.
Mensa Mensa IQ Logical Deduction Problems 4
All surgeons are doctors.
Some doctors are researchers.
Which conclusion must be true?