You Smart? Have you tried the World’s Shortest IQ Test

By Faith Mutete

Many people boast of their intelligence in comparison to others and what they can do better than the rest , but if you really want to know how smart you are the Cognitive Reflection Test CRT is what you should really take up and proof your intelligence.

Known to be the world’s shortest IQ test, it comprises only three questions.

The test was developed in 2005 by  Princeton psychologist Shane Frederick, the quiz assesses your ability to process information slowly and rationally, rather than jumping to quick conclusions. “

The most alarming thing about this test is that students from prestigious universities including Harvard and Yale have taken up this challenge and failed with only 17 percent received a perfect score.

Think you have what it takes? Give it a shot! Here are the three 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 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?

Pretty daydreaming


  1. $0.05. If you guessed 10 cents, you’re not alone. However, if that were the case, the bat and ball would cost $1.20—not $1.10. On the other hand, purchasing a 5 cent ball and a bat priced at $1.05 (which is $1 more expensive than 5 cents) would total $1.10, instead.
  2. 5 minutes. Although you might have answered 100 minutes, the actual time is a little less than that. Since the question reveals that it would take 5 minutes for 1 widget machine to make 1 widget, you can determine that it would take 5 minutes for 100 widget machines to make 100 widgets.
  3. 47 days. At first, your gut might tell you it would take 24 days. But remember: Since the area of the lake covered in lily pads doubles every day, a patch that covers half the lake would fully cover it in just one day. Subtract one day from 48 days, and what do you get? 47 days.