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Number Theory
Divisibility
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Concept Quizzes
Is 12345 divisible by 5?
Note: 12345 is divisible by 5 if it can be divided into groups of 5 with nothing left over.
Excel in math and science
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by Brilliant Staff
Excel in math and science
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Our wiki is made for math and science
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by Brilliant Staff
A number that consists entirely of 1s (like 1, 11, 111, etc.) is called a repunit. How many digits long is the smallest repunit that is divisible by 9?
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For how many different values of \(A\) is \(27A4\) (a four digit number where the third digit is \(A\)) divisible by 6?
Excel in math and science
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For how many different values of \(A\) is the three digit number \(3A6\) even?
Note: \(A\) can be any of the 10 digits from 0 to 9.
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by Brilliant Staff