Since lockdown began we have noticed everyone’s love for quizzes and testing their brain power, and we have another tricky one for you to try out.
Have you ever wondered what your IQ is but never had the patience to do a lengthy test? Then you could now find out within a matter of minutes.
Most IQ tests have endless questions and can take hours to complete so if those don’t take your fancy we may have the perfect solution for you.
The world’s shortest IQ test. But don’t be fooled it’s just as tough as the rest.
The IQ test is made up of just three maths questions and shouldn’t take too long to complete.
Originally published in 2005 by Professor Shane Federick, as part of a research paper named the Cognitive Reflection Test, it has resurfaced online with those keen to find out their intelligence, according to The Mirror.
The study had 3,000 participants from a range of educational backgrounds, including some Harvard and Yale University students.
However only 17 per cent managed to bag a three out of three score, resulting in 83 per cent of people failing. But will you?
The author says: “The three items on the CRT are “easy” in the sense that their solution is easily understood when explained, yet reaching the correct answer often requires the suppression of an erroneous answer that springs “impulsively” to mind.”
So without further ado, scroll down to find the questions, answers and theory behind them.
(1) A bat and a ball cost $1.10 in total. The bat costs $1.00 more than the ball. How much does the ball cost? _____ cents
(2) If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets? _____ minutes
(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? _____ days
The paper quotes Jensen, 1998, and says: “People with higher cognitive ability (or “IQ”) differ from those with lower cognitive ability in a variety of important and unimportant ways.
“On average, they live longer, earn more, have larger working memories, faster reaction times and are more susceptible to visual illusions.”
How do you think you fared?
The most common incorrect answers:
1. 10 cents
2. 100 minutes
3. 24 days
Professor Frederick continued: “Anyone who reflects upon it for even a moment would recognise that the difference between $1 and 10 cents is only 90 cents, not $1 as the problem stipulates.
“In this case, catching that error is tantamount to solving the problem, since nearly everyone who does not respond ’10 cents’ does, in fact give the correct response.”
The correct answers:
1. 5 cents
2. 5 minutes
3. 47 days
You can read about the full test and paper here.
The answers explained:
If you’re as confused as we are, thankfully, Presh Talwalkar, from The Joy of Game Theory: An Introduction to Strategic Thinking, explains the answers on his blog.
1. Say the ball costs X. Then the bat costs $1 more, so it is X + 1. So we have bat + ball = X + (X + 1) = 1.1 because together they cost $1.10. This means 2X + 1 = 1.1, then 2X = 0.1, so X = 0.05. This means the ball costs 5 cents and the bat costs $1.05
2. If it takes five machines 5 minutes to make five widgets, then it takes one machine 5 minutes to make one widget (each machine is making a widget in 5 minutes). If we have 100 machines working together, then each can make a widget in 5 minutes. So there will be 100 widgets in 5 minutes.
3. Every day FORWARD the patch doubles in size. So every day BACKWARDS means the patch halves in size. So on day 47 the lake is half full.