Odd one out IQ test
Which number breaks the rule?
Odd-one-out puzzles reward a second look because the obvious visual pattern is often hiding a stricter rule.
Quick answer
Answer: 48
16, 25, 36, and 64 are perfect squares. They are 4 squared, 5 squared, 6 squared, and 8 squared. 48 is not a perfect square.
How to solve it
1
Look for a property the numbers might share.
2
Check whether they fit common number families.
3
Notice that most of the numbers are perfect squares.
4
Remove the number that does not fit that rule.
What this tests
Category detection
Mathematical reasoning
Inhibition of fast guesses
Rule verification
IQFlow
Try a broader reasoning check
IQFlow combines multiple short reasoning tasks so one puzzle does not have to carry the whole story.