80% of people fail world's shortest IQ test that only has three questions

If you want to do a quick IQ test, then the world's shortest one has only three questions - but most aren't able to pass it.

One of those who took the test and admitted they 'failed immediately' was TikToker @chibimallo, who read out all the questions without giving out the answers. Check it out:

Importantly, she pointed out that how you did on an IQ test didn't determine how smart you were.

People think IQ is a measure of intelligence, as though it was as easy as slapping a number on someone's brain like you're making a league table of smart people.

Some scientists have disputed the usefulness of IQ tests in measuring intelligence, and any test is going to struggle to pick out all the ways a person can be smart.

Created by MIT professor Shane Frederick in 2005, the Cognitive Reflection Test proved more difficult than you might assume as the vast majority of people who gave it a go couldn't get everything right.

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When he first created the test he put 3,428 people through it and only 17 percent were able to get all of the questions right, so can you do better?

Here's the questions:

1. A bat and a ball cost $1.10 in total, the bat costs $1 more than the ball. How much does the ball cost?
2. If it takes five machines five minutes to make five widgets, how long would it take 100 machines to make 100 widgets?
3. In a lake there's a patch of lily pads. Every day the patch doubles in size, if it takes 48 days for the patch to cover the entire lake how long would it take for the patch to cover half of the lake?

These questions were designed to 'yield impulsive erroneous responses' where your brain would alight on what sounds like the right answer before you can go 'hang on' and realise you've jumped to the wrong conclusion.

As for the answers, for the first brain teaser the answer is that the ball costs five cents, meaning that the bat costing a dollar extra makes it $1.05 and combined they'd set you back $1.10.

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For question number two the right answer is of course five minutes, because if it takes five machines five minutes to make five widgets then one machine makes a widget in five minutes, so 100 of them all going at the same time will have the job done in five minutes.

Finally, the patch of lily pads which doubles in size every day and eventually covers the entire lake on day 48 could cover half of it on day 47.

That last day of doubling in size takes it from half a lake's worth of coverage to full, so don't fall into the trap of thinking the answer is 24 days.

If you got at least one question right then you're doing better than the 33 percent of responders who went zero for three in testing the world's shortest IQ test.