Cognitive Reflection Verbal and Logic Puzzles Questions and Answers

Question 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?

Accepted Answer

5 cents

Answer

Let the cost of the ball be X. The cost of the bat is X + $1.00. Together, they cost X + (X + $1.00) = $1.10. This simplifies to 2X + $1.00 = $1.10. Subtracting $1.00 from both sides gives 2X = $0.10. Therefore, X = $0.05, or 5 cents. The intuitive answer, 10 cents, is incorrect because if the ball were 10 cents, the bat would be $1.10, for a total of $1.20.

Question 2

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?

Accepted Answer

47 days

Answer

If the patch of lily pads doubles in size every day, then on any given day, it was half the size the day before. If the lake is fully covered on day 48, it must have been half-covered on the preceding day, which is day 47.

Question 3

A farmer had 17 sheep. All but 9 died. How many sheep are left?

Accepted Answer

9

Answer

The phrase 'All but 9' is a linguistic trick. It means that all sheep died *except for* 9. Therefore, 9 sheep are left. The intuitive calculation (17 - 9 = 8) is a misinterpretation of the sentence structure.

Question 4

Which of the following logical conclusions is valid based on the premises?

Premise 1: All penguins are birds.
Premise 2: Some birds cannot fly.

Accepted Answer

The conclusion cannot be determined from the premises.

Answer

While it is factually true that penguins cannot fly, this conclusion cannot be logically derived from the given premises. The group 'some birds' that cannot fly might or might not include penguins. We only know that the category of non-flying birds exists, but we don't know which specific birds fall into it based on the information given. Therefore, a definitive conclusion about penguins' ability to fly cannot be made.

Question 5

You are a bouncer at a bar and must enforce the rule: 'If a person is drinking alcohol, they must be over 21.' You see four people: one drinking a beer, one drinking a soda, one who is 30 years old, and one who is 16 years old. Which person or people do you need to check to ensure the rule is not being broken?

Accepted Answer

The person drinking beer and the 16-year-old.

Answer

This is a classic logic puzzle known as the Wason Selection Task. To test the rule 'If P, then Q', you must check the case where P is true (the person drinking beer, to see if they are over 21) and the case where Q is false (the 16-year-old, to see if they are drinking alcohol). Checking the 30-year-old is irrelevant (the rule doesn't care what they drink), and checking the soda drinker is also irrelevant (the rule only applies to alcohol drinkers).

Cognitive Reflection Test Practice Test

Cognitive Reflection Test Practice Test

Cognitive Reflection Verbal and Logic Puzzles Questions and Answers