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Mathematica Teacher's Edition

Built-in Functions

Mathematical Functions

Numerical Functions

Round

Round[x] gives the integer closest to x.

Mathematical function (see Section A.3.10).
Examples: Round[2.4]; Round[2.6]; Round[-2.4]; Round[-2.6].
Round rounds numbers of the form x.5 toward the nearest even integer.
Round[x] returns an integer when x is any numeric quantity, whether or not it is an explicit number.
Example: Round[Pi^2].
For exact numeric quantities, Round internally uses numerical approximations to establish its result.
See The Mathematica Book on the web: Section 1.1.3 and Section 3.2.2.
See also: IntegerPart, Floor, Ceiling, Chop.

Further Examples