A landmark number is a number that makes math simpler by virtue of it being easy to relate to and calculate with, such as the number "10." Most landmark numbers are multiples of 10.

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Landmark numbers are familiar landing places that make solving math problems easier, such as multiples of tens or hundreds. Familiarity with these numbers is vital to understanding numbers and their relationships with on...

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Friendly numbers are individual numbers that make up part of what is known as a friendly pair. Friendly numbers always come in sets of two, and they are known for having a positive density.

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In math, a composite number is a whole number that can be divided evenly by a number other than itself and one. If a number cannot be divided evenly in this way, it is called a prime number.

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The number notated by "e" is a famous irrational number known as Euler's number that is approximately equal to 2.72. The number "e" has no final digit and has been calculated accurately to over one trillion digits.

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In mathematics, a factor of a base number is any number that can be evenly divided into the base number. Due to this definition, a factor can only be less or equal to the original base number. Although all whole numbers ...

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Helpful worksheets for practicing math depend on the child’s grade level; for example, first-graders benefit from number order and missing number worksheets, while middle school students benefit from worksheets covering ...

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