Mensa IQ Test Mensa IQ Odd One Out Puzzles

Question 1

Which number does NOT belong in this group: 2, 3, 5, 7, 9, 11, 13?

Accepted Answer

9

Answer

All other numbers are prime (divisible only by 1 and themselves), but 9 = 3 × 3 is composite. It is the only number in the set that has factors other than 1 and itself.

Question 2

Which shape does NOT belong: circle, oval, sphere, square?

Accepted Answer

Square

Answer

Circle, oval, and sphere are all based on curves with no straight edges or angles. A square has straight sides and right angles, making it fundamentally different from the curved shapes.

Question 3

Which number is the odd one out: 1, 4, 9, 15, 25, 36?

Accepted Answer

15

Answer

1, 4, 9, 25, and 36 are all perfect squares (1², 2², 3², 5², 6²). 15 is not a perfect square — it cannot be expressed as any integer multiplied by itself.

Question 4

Which word does NOT belong: Dog, Cat, Fish, Chair, Bird?

Accepted Answer

Chair

Answer

Dog, cat, fish, and bird are all living creatures (animals). Chair is an inanimate piece of furniture, making it categorically different from the rest.

Question 5

Which number does NOT fit the pattern: 8, 27, 64, 100, 125?

Accepted Answer

100

Answer

8=2³, 27=3³, 64=4³, 125=5³ are all perfect cubes. 100 is not a perfect cube (4.64³ ≈ 100), making it the odd one out. 100 is actually 10², a perfect square.

Mensa Practice Test Practice Test

Mensa Practice Test Practice Test

Mensa IQ Test Mensa IQ Odd One Out Puzzles