Primary Schools

Glossary

This limited glossary contains commonly understood working definitions of some
mathematical terms.

algorithma logical, arithmetical or computational procedure that if correctly applied ensures the solution of a problem
analogue clocka clock on which hours, minutes and sometimes seconds are indicated by hands on a dial
area unit of area equal to 100 square metres
associativean operation such as multiplication or addition is associative if the same answer is produced regardless of the order in which the elements are grouped, e.g.
(2 + 3) + 5 = 10, 2 + (3 + 5) = 10
cardinal numbera number denoting quantity but not order in a set
commutativegiving the same result irrespective of the order of the elements in an operation, e.g. for addition and multiplication 6 + 2 = 8, 2 + 6 = 8, 5 x 7 = 35, 7 x 5 = 35
composite numbera number with more than two factors that is not a prime number, e.g. 6, 10
denominatorthe divisor in a fraction diameter a straight line connecting the centre of a circle with
two points on the perimeter
distributivethe same result is produced when multiplication is performed on a set of numbers as when performed on the members of the set individually, e.g. 5 x 4 = (3 + 2) x 4 = (3 x 4) + (2 x 4)
dividenda number or quantity to be divided by another number or quantity
divisora number or quantity to be divided into another number or quantity
equationa mathematical sentence with an equals sign
hectarea unit of area equal to 100 ares
line symmetrya shape has line symmetry if one half of the shape can be folded exactly onto the other half
number sentencean equation or statement of inequality, e.g. 4 + x = 11, 4 2 < 12 or 2 + 5 = 7
numeratorthe number above the line in a fraction
ordinal numbera number denoting relative position in a sequence, e.g. first, second, third perimeter the sum of the length of the sides of a figure or shape
prime factora factor that is a prime number
prime numbera whole number that has only two factors, itself and 1, e.g. 2, 3, 7
productthe result of multiplying two numbers
quotientthe result of dividing one number by another number
radiusa line from the centre of a circle to a point on the circumference; a radius is half of the diameter
ratiothe relationship between two numbers of the same kind; e.g. the ratio of 2 kg to 6 kg is 2 : 6
subitisetell at a glance, without counting, the number of items in a set
subtrahendthe number to be subtracted from another number, e.g. 10 - 4 (4 is the subtrahend)
tessellationshapes tessellate if they fit together exactly, form a repeating pattern and make an angle of 360° at the points of contact
variablea letter or symbol that stands for a number, for example y + 7 = 12



 
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