Here the 3-item CRT test for ‘cognitive reflection’ developed at Princeton. Average Carnegie Mellon and Harvard undergraduate scores for this test range from 1.4-1.5 out of 3! The answers can be found in the comments below. Please add your own comments letting others know how you got on with this test.
Cognitive Reflection Test (CRT)
Are you ready….
Take your time…
(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 Cognitive Reflection Test has a large correlation with IQ. But it is designed to measure the tendency to override automatic problem solving responses that are incorrect and to use your meta-awareness to double check your thoughts and find the correct response. For this reason, how people do on the CRT can be a good predictor of how well people do in overcoming cognitive biases – of which there are many that we may be susceptible to on a day-by-day basis (Ref).
If you are interested in using meta-awareness & other strategies to augment IQ and help with cognitive biases, sign up to the free content below:
1) 5 cents
2) 5 minutes
3) 47 days
3 out of 3, and I’m just 17 years old!!!!!!!!!!!!!!!!!!!
1) 10 cents
2) 5 min
3) 47 days
Too easy, sorry.
The ball costs 10 cents. 100 machines will make 100 widgets in 5 minutes. It will take 47 days to cover half the lake with lily pads. I had to slow down and read the questions, because my first thoughts were to quick and then I would catch myself and then I would see the true answer.
I probably should have given myself a little more time to wake up completely.
Good Day
Gerald Peatross
Yes, I love these brain openers!
My problem is,I , many times, when I guess wrong, I can never find the logic of what I did wrong or the correct route to the winning answer.
I know there is a pattern to take to reach the correct answer, but I am lost on how to find it.
I’m talking about those “matrix “[?] games] The one where you have 4 patterns [or 3] across and 3 or 4 vertical patterns. Example.
5 cents, 5 minutes, 47 days…
well over 85% of respondents (including Harvard and Yale grads, and a less % of MIT grads) think the ball will cost 10 cents (wrongo dongo), so don’t feel too bad if you missed that one, the correct answer is 5 cents…
other two are no-brainers…
too bad you are wrong!
1)10 cents
2)5 min
3)24 days
5 cents, 5 min, 47 days. easy peasy.
3
Thomas you got it Wrong it was superbly easy
1)5 cents
2)5 minutes
3)47 days
It’s Funny because I am only twelve years old and half of Harvard or Carnegie got it wrong so Im proud of myself
Ball is 5 cents
the ball costs 5 cents
I am 99% sure you looked at the comments
It’s 5 cents, 5 mins, and 47 days, sorry!
Lol I’m fifteen and got them
-5¢
-5 min
-47 days
Not too hard lol
-5 cents
-5 minutes
–47 days
Too easy for a fifteen year old.
Me too, but i’m 13
5 cents, 5 minutes, 47 days.
I’m a ramblin’ wreck from Georgia Tech and a hell of an engineer!
How did the MIT (the Georgia Tech of the north) grads do?
Cant make sense of the bat and ball, the other two make sense. Can anyone explain it to me?
5 cents
“A bat and a ball cost $1.10 in total. The bat costs $1.00 more than the ball.”
Ball = X
Bat = X + $1.00
Thus, if X = $0.05, then X + $1.00 = $1.05
Therefore, the Ball costs $0.05
and the bat costs $1.05
and the total cost is $1.10
The bat costs a dollar more than the ball so the total cost is the cost of one ball plus the cost of a ball plus a dollar. So $1.10 = $1 plus the cost of two balls. So $0.10 is the cost of two balls.
$1.05 – $.05 = $1.00