The World’s Shortest IQ Test Developed by MIT Professor. Only 20% Get All Three Questions Right!

The world’s shortest IQ test is proving to be quite tough, with only 17 percent 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.

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 are 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 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…

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1. 5 cents (Ball = $.05, bat – $1.05)

2. 5 minutes (Each machine can make one widget every five minutes, no matter the amount of machines.)

3. 47 days (If it doubles each day, the pond would be half covered one day before being fully covered)

 

How’d you do?!