Level 3 · Hard
Which one is the odd one out?
- A10
- B36
- C30
- D60
- E40
Show the answer and the rule
- All the others are multiples of 10. This one is not.
Brain zone
Which one doesn't belong? Pictures, shapes, numbers and words.
Five levels
Start where it feels easy, then step up. Each round is new.
Ages 5–7 · 10 puzzles
Ages 7–9 · 10 puzzles
Ages 9–11 · 10 puzzles
Ages 11–13 · 10 puzzles
Ages 13+ · 10 puzzles
What it trains
Odd one out trains classifying: finding what most things have in common, and noticing the one that breaks the group — by category, shape, or a number property like even, square or prime.
How to solve it
Try one
Level 3 · Hard
Not these puzzles. They are reasoning puzzles like those found in IQ-style tests, made for practice and fun, and they don't give a score. If you'd like a score, try our IQ-style practice test: it gives a practice score for learning and fun, not a clinical assessment.
Each level shows suggested ages, but start where it feels easy and move up after a round with two or three stars.
Yes. Every puzzle type prints as a black-and-white sheet with a separate answer key, on A4 or US Letter.
More brain puzzles
Which picture is the reflection in the mirror line?
Picture sudoku for little ones, then 4×4, 6×6 and 9×9.
Use the clues to work out who has what.
Things are sorted into groups. What's the sorting rule?