Question: A snail is at the bottom of a forty (40) foot wall. Each day it climbs up four feet, but at night it slips back three feet. How many days will it take for the snail to climb to the top of the wall?

Alternative Question Phrasing:

Follow-up questions:

How did you arrive at this answer?
Was there any formula you used?

Question Details:

Question Type:

Unconventional

Skills:

Basic – Critical Thinking,Basic – Mathematics,Complex Problem Solving

Abilities:

Cognitive – Mathematical Reasoning,Cognitive – Number Facility (Math Solving Speed),Cognitive – Visualisation

Work Activity (Task):

Mental Processes – Processing Information

Question Frequency

Question Difficulty

What to look for in an answer:

If the candidate is able to quickly able do that basic math.
Look for the candidate’s thought process.

Red Flags to Watch For:

If the candidate takes too long.
Candidate appears to be nervous and confused.
Gives a wrong answer and has no proper reasoning.

Sample Answer:

The answer is 37 days. On the 36th day, the snail is at 36 feet. During the daytime of the 37th day, it will climb up 4 feet, which is 36+4=40 feet, and scale the wall. Once it has scaled the wall, it won’t slip the 3 feet down any longer.

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