Odd one out
14 free practice questions with explanations
PassNova has 14 free Logical & Abstract Reasoning practice questions on Odd one out, each with a clear explanation. Practise them in the browser with instant feedback — 100% free, no sign-up, on any device. Updated for 2026.
Odd one out: example questions & answers
14 worked examples with answers and explanations below. Practise them in the browser with instant feedback on every answer.
Which is the odd one out: 3, 5, 9, 11, 17?
- A3
- B5
- C9✓
- D17
Answer: All the numbers are prime except 9, which equals 3 x 3, so 9 is the odd one out.
Which is the odd one out: 2, 4, 6, 9, 10?
- A2
- B6
- C9✓
- D10
Answer: All the numbers are even except 9, which is odd, so 9 is the odd one out.
Which is the odd one out: Apple, Banana, Carrot, Orange?
- ACarrot✓
- BApple
- CBanana
- DOrange
Answer: Apple, banana and orange are fruits, while a carrot is a vegetable, so carrot is the odd one out.
Which is the odd one out: Square, Triangle, Circle, Rectangle?
- ACircle✓
- BTriangle
- CSquare
- DRectangle
Answer: A square, triangle and rectangle all have straight sides and corners, while a circle has none, so circle is the odd one out.
Which is the odd one out: 16, 25, 36, 40, 49?
- A16
- B25
- C40✓
- D49
Answer: 16, 25, 36 and 49 are perfect squares, but 40 is not, so 40 is the odd one out.
Which is the odd one out: Dog, Cat, Sparrow, Horse?
- AHorse
- BSparrow✓
- CCat
- DDog
Answer: A dog, cat and horse are four-legged mammals, while a sparrow is a two-legged bird, so sparrow is the odd one out.
Which is the odd one out: 8, 27, 64, 100, 125?
- A8
- B64
- C100✓
- D125
Answer: 8, 27, 64 and 125 are cube numbers, but 100 is a square not a cube, so 100 is the odd one out.
Which is the odd one out: Red, Blue, Loud, Green?
- ABlue
- BGreen
- CLoud✓
- DRed
Answer: Red, blue and green are colours, while loud describes sound, so loud is the odd one out.
Which is the odd one out: 21, 33, 37, 39?
- A21
- B33
- C37✓
- D39
Answer: 21, 33 and 39 are all divisible by 3, but 37 is prime, so 37 is the odd one out.
Which is the odd one out: January, March, June, July?
- AJune✓
- BJuly
- CMarch
- DJanuary
Answer: January, March and July all have 31 days, while June has 30, so June is the odd one out.
Which is the odd one out: Copper, Iron, Plastic, Gold?
- APlastic✓
- BIron
- CGold
- DCopper
Answer: Copper, iron and gold are metals, while plastic is not, so plastic is the odd one out.
Which word is the odd one out: BAT, CAT, RAT, DOG?
- ADOG✓
- BRAT
- CBAT
- DCAT
Answer: BAT, CAT and RAT all end in 'AT', while DOG does not, so DOG is the odd one out.
Which is the odd one out: 12, 18, 24, 30, 31?
- A12
- B18
- C24
- D31✓
Answer: 12, 18, 24 and 30 are all multiples of 6, but 31 is not, so 31 is the odd one out.
Which is the odd one out: 5, 10, 15, 22, 25?
- A5
- B10
- C22✓
- D25
Answer: 5, 10, 15 and 25 are all multiples of 5, but 22 is not, so 22 is the odd one out.