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Number Theory

Modular Arithmetic Operations

Excel in math and science

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Concept Quizzes

Modular Arithmetic Operations Warmup
Addition and Subtraction
Parity (Odd/Even)
Multiplication
Exponentiation
Multiplicative Inverses

Challenge Quizzes

Level 1
Level 2
Level 3

Modular Arithmetic Operations: Level 1 Challenges

What is the last digit when

\[ 1234 \times 5678 \]

is multiplied out?

8 2 4 6

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by Chung Kevin

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If today is a Monday, then what day will it be 100 days later?

Wednesday Sunday Friday Monday

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by Chung Kevin

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\[ \LARGE \color{red} 5^{\color{blue}8^{\color{green}{12}^{\color{purple}{15}^{\color{brown}{104}}}}} + \color{red}1\]

Determine the smallest prime divisor of the gigantic number above.

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by Martin Soliman

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One of the seven goblets above is made of real gold. If you start counting at A and wind back and forth while counting (A, B, C, D, E, F, G, F, E, D, ...), then the golden goblet would be the \(1000^\text{th}\) one that you count.

Which one is the golden goblet?

A B C D E F G

Excel in math and science

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by Psalm Lemuel Guevarra

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If \(a\) is a negative odd number and \(b\) is a positive even number, then which of the following must be a positive even number?

\[a+b\] \[ab\] \[b-a\] \[-ab\]

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by Anuj Shikarkhane

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Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

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Modular Arithmetic Operations

Excel in math and science

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Concept Quizzes

Challenge Quizzes

Modular Arithmetic Operations: Level 1 Challenges

Excel in math and science

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Excel in math and science

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Our wiki is made for math and science

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Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

Master advanced concepts through explanations, examples, and problems from the community.

Used and loved by 4 million people

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Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

Master advanced concepts through explanations, examples, and problems from the community.

Used and loved by 4 million people

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Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

Master advanced concepts through explanations, examples, and problems from the community.

Used and loved by 4 million people

Learn from a vibrant community of students and enthusiasts, including olympiad champions, researchers, and professionals.

Master advanced concepts through explanations,
examples, and problems from the community.

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

Master advanced concepts through explanations,
examples, and problems from the community.

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

Master advanced concepts through explanations,
examples, and problems from the community.

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

Master advanced concepts through explanations,
examples, and problems from the community.

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

Master advanced concepts through explanations,
examples, and problems from the community.

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

Master advanced concepts through explanations,
examples, and problems from the community.

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

Master advanced concepts through explanations,
examples, and problems from the community.

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.