What does solving a problem by 'trial and error' mean?
AnswerTrying different approaches until one works
Trial and error means attempting solutions, learning from the failures and adjusting until something works.
Education · Facts & stats
Problem facts & stats
7 fact-checked facts about problem solving and famous problems, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
In a standard Sudoku, each row must contain which digits exactly once?
Answer1 to 9
A standard Sudoku is a 9×9 grid where every row, column and 3×3 box holds each digit from 1 to 9 once.
Going deeper
In the Monty Hall problem, what is your chance of winning the car if you always switch doors?
Answer2/3
Your first pick is right only one time in three, so switching wins in the remaining two out of three cases.
What does the 'travelling salesman problem' ask for?
AnswerThe shortest round trip that visits every city once
It seeks the shortest route through a set of cities and back home, and gets very hard as more cities are added.
What is 'rubber duck debugging'?
AnswerExplaining a problem aloud, step by step, to an object
Talking through code line by line, even to a rubber duck, often helps programmers spot their own mistakes.
Expert level
Which mathematician wrote the classic 1945 problem-solving guide 'How to Solve It'?
AnswerGeorge Pólya
George Pólya's method is to understand the problem, devise a plan, carry it out and look back.
How many Millennium Prize Problems did the Clay Mathematics Institute announce in 2000?
Answer7
The list includes famous open questions such as the Riemann hypothesis and P versus NP.
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