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Improper fraction A positive fraction whose numerator is greater than or equal to its denominator, or the

Independent events Events that have no effect on each other.

Indirect measurement A measurement in which no direct comparison is made between the object being

measured and a physical standard.  Or, a measurement obtained by calculation

Inequality   A mathematical sentence formed by placing an inequality sign between two expressions.

Infinite set A set with an unlimited number of elements

Integers   The whole numbers and their opposites: . . . -2, -1, 0,1,2 .........

Interest   The amount of money paid for the use of money.

Interpolation   A method of approximation.

Intersecting lines Two straight lines that have one and only one point in common

Intersecting planes Two planes that have one and only one line in common

Intersection (of sets) The set of all elements which belong to both of two sets. ,P n Q" is read "P intersection Q"

Inverse operations   Operations that undo each other, such as addition and subtraction or multiplication and division.

Irrational number   All real numbers that are not rational.

Isosceles triangle A triangle with at least two sides congruent.