{"id":44542,"date":"2025-05-26T13:40:47","date_gmt":"2025-05-26T05:40:47","guid":{"rendered":"https:\/\/www.wukongsch.com\/blog\/?p=44542"},"modified":"2025-10-16T09:48:48","modified_gmt":"2025-10-16T01:48:48","slug":"what-is-the-3-question-iq-test","status":"publish","type":"post","link":"https:\/\/www.wukongsch.com\/blog\/what-is-the-3-question-iq-test-post-44542\/","title":{"rendered":"The World Shortest IQ Test Ever? Try the 3-Question IQ Test!"},"content":{"rendered":"
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Recently, one particular \u201cIQ test\u201d has gone viral across social media: the 3-question IQ test, also known as the Cognitive Reflection Test. Despite its simplicity, it has sparked deep conversations about intelligence, problem-solving, and how we think.<\/div>\n
In this article, we\u2019ll unpack what the 3-question IQ test really is, where it came from, what it does and doesn\u2019t measure, and whether it has a place in the classroom or at home as a learning tool.<\/div>\n
Want to see how your child\u2019s IQ compares to peers? Our guide on the IQ test for 12-year-olds<\/a> breaks down score ranges and interpretation tips.<\/div>\n

<\/span>What Is the 3-Question IQ Test?<\/span><\/h2>\n

Definition and Origin<\/h3>\n
The so-called 3-question IQ test<\/em> is not actually a full IQ test. It\u2019s a condensed version of the Cognitive Reflection Test (CRT), a short assessment developed by behavioral economist Shane Frederick in 2005.<\/div>\n
Frederick designed the CRT to measure a person\u2019s tendency to override an initial, incorrect “gut” response and engage in further reflection to find the correct answer. It\u2019s not about how smart you are in the traditional IQ sense, it\u2019s about how you think.<\/div>\n
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Source: Shane Frederick. “Cognitive Reflection and Decision Making.” Journal of Economic Perspectives<\/em><\/div>\n<\/blockquote>\n

<\/span>What Are the 3 Questions of the World Shortest IQ Test?<\/span><\/h2>\n

\"3<\/p>\n

Here are the original three CRT questions:<\/div>\n
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? <\/strong><\/div>\n
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Common wrong answer: 10\u00a2<\/div>\n
Correct answer: 5\u00a2 (The bat is $1.05, and the ball is $0.05)<\/div>\n<\/blockquote>\n
2.If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets? <\/strong><\/div>\n
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Common wrong answer: 100 minutes<\/div>\n
Correct answer: 5 minutes (Each machine makes 1 widget in 5 minutes)<\/div>\n<\/blockquote>\n
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 to cover half the lake? <\/strong><\/div>\n
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Common wrong answer: 24 days<\/div>\n
Correct answer: 47 days (The lake is half-covered the day before it\u2019s fully covered)<\/div>\n<\/blockquote>\n
Each question is designed to trigger an intuitive but incorrect answer, prompting deeper thought to arrive at the correct one.<\/div>\n

<\/span>What Does the Shortest IQ Test Actually Measure?<\/span><\/h2>\n

Fast vs. Reflective Thinking<\/h3>\n
To understand this test\u2019s purpose, we can look to Nobel Prize-winning psychologist Daniel Kahneman, who described two systems of thought in his book Thinking, Fast and Slow<\/em>:<\/div>\n