Level 3 · Hard
Which one is the odd one out?
- A10
- B36
- C30
- D60
- E40
Show the answer and the rule
Answer: B
- All the others are multiples of 10. This one is not.
Brain zone
Odd one out puzzles
Which one doesn't belong? Pictures, shapes, numbers and words.
Five levels
Choose your level
Start where it feels easy, then step up. Each round is new.
Easy
Ages 5–7 · 10 puzzles
Medium
Ages 7–9 · 10 puzzles
Hard
Ages 9–11 · 10 puzzles
Tricky
Ages 11–13 · 10 puzzles
Expert
Ages 13+ · 10 puzzles
What it trains
Odd one out
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
Three steps
Step 1: Look at all of them before you choose.
Step 2: Find something that all but one share.
Step 3: Check the odd one really is the only one that's different.
Try one
An example puzzle
Questions
Is this an IQ test?
No. These are reasoning puzzles like those found in IQ-style tests, made for practice and fun. We don't measure intelligence or give IQ scores.
Which level should my child start at?
Each level shows suggested ages, but start where it feels easy and move up after a round with two or three stars.
Can I print these puzzles?
Yes. Every puzzle type prints as a black-and-white sheet with a separate answer key, on A4 or US Letter.
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Which picture is the reflection in the mirror line?
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Picture sudoku for little ones, then 4×4, 6×6 and 9×9.
Logic grids
Use the clues to work out who has what.
Spot the rule
Things are sorted into groups. What's the sorting rule?