A deceptively simple maths brain teaser is sweeping across the UK, leaving thousands of Brits scratching their heads in confusion. What appears to be a straightforward question about brothers' ages has proven to be an astonishingly tricky puzzle that only 5% of people can solve correctly.
The Puzzle That's Breaking the Internet
The viral conundrum presents participants with a seemingly innocent question: "When I was 4 years old, my brother was half my age. Now I'm 18, how old is my brother?"
Most people's initial instinct leads them to a quick answer that feels mathematically sound - but there's a clever twist that catches nearly everyone out.
The Common Mistake Everyone Makes
The majority of respondents quickly calculate that half of 4 is 2, suggesting a two-year age difference. Following this logic, they conclude that when the speaker turns 18, their brother must be 16.
This answer seems perfectly reasonable at first glance, but it contains a fundamental flaw in understanding how age differences work over time.
The Correct Solution Revealed
The accurate answer is that the brother is now 16 years old. Here's why:
When the speaker was 4, their brother was half that age - 2 years old. This establishes a fixed age difference of 2 years between them.
Age differences remain constant throughout life. Therefore, when the speaker reaches 18, their brother will always be 2 years younger, making him 16 years old.
Why This Puzzle Is So Tricky
This brain teaser plays on our cognitive biases towards recent mathematical operations. Our brains gravitate toward the "half" calculation we just performed, making us want to apply it again to the current age rather than recognizing the constant relationship.
The puzzle has sparked lively debates across social media platforms, with many users passionately defending their incorrect answers before having the "aha!" moment when the solution is properly explained.
Maths educators emphasize that this type of puzzle brilliantly demonstrates the importance of reading questions carefully and thinking beyond immediate calculations. It serves as a perfect reminder that some problems require logical reasoning rather than just mathematical operations.
