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
What is the fewest number of moves needed to solve the Tower of Hanoi with 3 disks?
Answer7
With n disks the minimum is 2^n − 1 moves, and a larger disk may never sit on a smaller one.
Which mathematician solved the Seven Bridges of Königsberg problem?
AnswerLeonhard Euler
In 1736 Euler proved no walk can cross all seven bridges exactly once, laying the foundations of graph theory.
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
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.
In 1900, David Hilbert published a famous list of how many unsolved mathematics problems?
Answer23
Hilbert's problems, presented around the 1900 International Congress of Mathematicians in Paris, shaped 20th-century mathematics.
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