Cognitive Reflection Test Cognitive Reflection Reflective Reasoning Under Uncertainty

Question 1

A car travels 60 miles at 30 mph, then 60 miles at 60 mph. What is the average speed for the whole trip?

Accepted Answer

40 mph

Answer

45 mph

Answer

50 mph

Answer

55 mph

Question 2

You have two ropes that each burn in exactly 60 minutes but unevenly. How do you measure 45 minutes?

Accepted Answer

Light rope 1 from both ends and rope 2 from one end; when rope 1 finishes, light rope 2's other end

Answer

Burn both ropes from one end simultaneously

Answer

Cut each rope in half and burn the halves

Answer

Burn rope 1 fully, then half of rope 2

Question 3

Three people can paint three walls in three hours. How long will it take six people to paint six walls?

Accepted Answer

3 hours

Answer

1.5 hours

Answer

6 hours

Answer

12 hours

Question 4

A snail is at the bottom of a 10-foot well. Each day it climbs 3 feet; each night it slips back 2 feet. How many days to escape?

Accepted Answer

8 days

Answer

7 days

Answer

10 days

Answer

9 days

Question 5

If it takes 5 machines 5 minutes to make 5 widgets, how long does it take 100 machines to make 100 widgets?

Accepted Answer

5 minutes

Answer

100 minutes

Answer

20 minutes

Answer

1 minute

Question 6

You have a 3-liter and a 5-liter jug and need exactly 4 liters. What is the minimum number of steps to measure 4 liters?

Accepted Answer

3 steps

Answer

2 steps

Answer

4 steps

Answer

6 steps