A puzzle

It's easier to show you this, rather than explain it.

Look at the puzzle below:

• A bat and ball costs £1.10.

• The bat costs 1 pound (£) more than the ball.

• How much does the ball cost?

Most people would answer the obvious: the ball costs £0.10. And they'd be wrong.

The answer

If the bat costs £1.00 more than the ball, then the ball costs £0.05 (the bat costs £1.05).

This is a puzzle that initially seems easy, and most people who could objectively answer it correctly, wouldn't have, because they unknowingly took the path of least effort.

They settled on the first answer the was feasibly correct, rather than investing the small amount of effort required to check their initial judgement.

This is how people navigate the world, including digital products.

The bat and ball study

This bat and ball study, which was from the book 'Thinking, fast and slow', explains that more than 50% of students at Harvard, MIT and Princeton gave the intuitive (and incorrect) answer. 

At less selective universities, the failure rate was above 80%.