If a baseball and a bat cost $1.10 together, and the bat costs $1.00 more than the ball, how much does the ball cost?
Solution
5 cents. System 1 thinking often leads to mistakes in this type of problem.
A father and son are in a horrible car crash that kills the dad. The son is rushed to the hospital; just as he’s about to go under the knife, the surgeon says, “I can’t operate—that boy is my son!” How is that possible?
Solution
The surgeon is the boy’s mother. This puzzle illustrates the persistence of gender discrimination.
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?
Solution
47 days. To answer correctly, you need to ignore your system 1 and use your system 2.
Alan is smart, hard-working, impulsive, stubborn and jealous.
Ben is jealous, stubborn, impulsive, hard-working and smart.
Who should you hire?
Solution
They are the same, but a priming effect often make people prefer the first candidate.
