Only 20% of Harvard students aced this three-question IQ test...  how will YOU get on?

The world's shortest IQ test not only reveals your intelligence but also your level of patience. 

The test, called a Cognitive Reflection Test (CRT), consists of three math-based questions that target a person's ability to ignore their initial gut response in favor of a more rational thought process.

Many quickly assume the answers are simple, but the Yale University professor who created the exam warned it isn't as straightforward as it may seem.

Professor Shane Frederick created the CRT in 2005 and only 20 to 40 percent of students who have attempted it have passed.

Mathematical brain teasers are useful in helping people develop logical thinking by promoting brain stimulation and build visual and spatial reasoning skills.

A CRT measures a person's cognitive ability by assessing whether they can suppress spontaneous answers which ultimately end up being wrong and replace them with reflective and deliberate answers.

The first question asks: 'A bat and a ball cost $1.10 in total. The bat costs $1 more than the ball. How much does the ball cost?'

Frederick said that 10 cents would be the obvious choice, but that is wrong.

The reason? The difference between $1 and ten cents is 90 cents. Whereas the difference between $1.05 and 5 cents is one dollar, satisfying the parameters of the question.

The professor carried out a study with 3,428 people who were asked to solve his short IQ test.

He found that those who answered 10 cents were significantly less patient than those who answered correctly, IFLScience reported. 

The second question asks: 'If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?'

If you answered 100 minutes, you are once again wrong - the answer is five minutes.

The most obvious conclusion is to continue with the pattern that it would take 100 machines 100 minutes to make 100 widgets.

However, if each machine takes five minutes, even if you scale it up to 100 machines, it still takes each one only five minutes. 

The third question asks: 'In a lake, there is 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?'

Of the more than 3,000 people who took the test, most provided the wrong answer of 24 days, which at first glance makes sense because people's instinct is to halve the number of days.

Frederick said the answer is 47 because if the patch doubles each day and it's reached the full size of the pond, that means it was half the size one day earlier.

Although the test is meant to determine your IQ, if you got all or most of the questions wrong, you shouldn't feel inadequate, because students tested at some of the most prestigious schools in the country scored poorly.

Just 20 percent of Harvard University students answered all the questions correctly while 26 percent of Princeton University students and 48 percent at MIT got all three answers correct.