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The world’s shortest IQ test is proving to be quite tough, with only 17% of respondents answering correctly!

But how hard can it be when there are only three questions?

Created by MIT professor Shane Frederick back in 2005, the Cognitive Reflection Test has resurfaced recently…

Despite the length, more than 80 percent of takers fail to score 3 out of 3.

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Photo by Sean Gallup/Getty Images

While Frederick believes the test is “easy,” he says, “Reaching the correct answer often requires the suppression of an erroneous answer that springs ‘impulsively’ to mind.”

Here is the test…

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 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?

3. 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?

Here are the answers…

1. The ball costs $0.05. Many people guess the ball would cost 10 cents, but that would make the total $1.20 instead. However, if the ball is 5 cents and the bat costs a dollar more than the ball, that would make it cost $1.05. This would make the total $1.10.

2. It would take 5 minutes. You may have answered 100 minutes, but keep in mind that it would take 5 minutes for 1 widget machine to make 1 widget, so 100 machines could make 100 widgets in just 5 minutes.

3. It would take 47 days. At first, you might think it would take 24 days. But, since the lily pad-covered area doubles in size every day, the patch that covers half the area would double and cover the whole area in just one day. Subtract one day from 48 days and you get 47 days!

How did YOU score on the world’s shortest IQ test???