CCSLC Mathematics key terms

A way of expressing a number as a fraction of 100, so 25% means 25 out of every 100. Used to compare quantities and describe discounts, interest, and increases.

A number written as one whole number over another, such as 3/4, showing parts of a whole. The bottom number tells how many equal parts, the top how many are taken.

A number written using a point to show parts smaller than one, such as 2.75. The digits after the point represent tenths, hundredths, and so on.

Different fractions that name the same amount, such as 1/2 and 4/8. Multiplying or dividing top and bottom by the same number keeps the value unchanged.

Rewriting a fraction with the smallest possible whole numbers by dividing top and bottom by their highest common factor, for example 6/8 becomes 3/4.

A comparison of two or more quantities by division, written as 2:3 or 2 to 3. It shows how much of one thing there is for each part of another.

A statement that two ratios are equal, or a share of a total found using a ratio. Used to solve problems such as scaling recipes or sharing money fairly.

A problem-solving technique that first finds the value of one unit, then multiplies to get the required amount. For example, 5 pens cost $10, so 1 pen costs $2.

The value a digit has because of its position in a number. In 4,507 the 5 is worth 500 and the 4 is worth 4,000.

Replacing a number with a nearby simpler value, such as 4,872 to the nearest hundred being 4,900. Look at the next digit: 5 or more rounds up.

Finding a sensible approximate answer by rounding or using convenient numbers. Useful for checking whether a calculated result is reasonable before trusting it.

The agreed sequence for calculating expressions: brackets first, then powers, then multiplication and division, then addition and subtraction, working left to right within each level.

A number less than zero, written with a minus sign, used for temperatures below freezing, debts, or losses. Adding a negative moves left on the number line.

A whole number, positive, negative, or zero, with no fractional part. Examples include -7, 0, and 42.

A straight line on which numbers are placed in order by position, with negatives to the left of zero and positives to the right. Helps compare and add numbers.

A single value found by adding all the numbers in a set and dividing by how many there are. It summarises the whole set but can be pulled by extreme values.

The middle value of a set when the numbers are arranged in order. If there are two middle values, it is their average.

The difference between the largest and smallest values in a data set. It shows how spread out the data are but ignores everything in between.

A table that records how often each value or category occurs using tally marks or counts. It organises raw data so patterns can be seen more easily.

A graph using rectangular bars whose lengths show the size of each category. Bars may be vertical or horizontal and should be clearly labelled with a title and scale.

A circle divided into sectors, where each sector's angle represents a share of the whole. All sectors together must add up to 360 degrees or 100%.

A chart that distorts data through a cut axis, uneven scale, or exaggerated pictures, making differences look larger or smaller than they really are.

A measure from 0 to 1 of how likely an event is, where 0 means impossible and 1 means certain. For equally likely outcomes it is favourable outcomes divided by total outcomes.

One possible result of a situation involving chance, such as getting a head when flipping a coin. Listing all outcomes helps calculate probabilities fairly.

The complete list or set of all possible outcomes of a chance situation. For rolling one die, the sample space is 1, 2, 3, 4, 5, and 6.

Money paid for borrowing money or earned for saving it, usually a percentage of the amount over a period. Simple interest is calculated only on the original amount.

Interest calculated on the original amount plus interest already added, so the balance grows faster over time than with simple interest alone.

The original amount of money borrowed or invested, before any interest is added. Interest calculations start from this figure.

A reduction from the usual price, often given as a percentage. To find a sale price, calculate the percentage amount and subtract it from the original.

The cost of one item or one unit of measure, found by dividing total cost by quantity. Comparing unit prices shows which package is better value.

The option that gives the most value for money, judged by comparing unit prices or quality rather than by total price alone. Bigger packages are not always cheaper.

A plan listing expected income and planned spending over a period. It helps a person or household check whether spending fits within the money available.

Money received, such as wages, allowances, sales takings, or interest. It is the starting figure when planning a budget or calculating savings.

Money spent on goods, services, and bills during a period. Comparing expenditure with income shows whether a budget is balanced, in surplus, or in deficit.

The relationship between a distance on a map or drawing and the real distance it represents, such as 1 cm to 5 km. Used to convert measurements accurately.

The total distance around the outside edge of a flat shape, found by adding the lengths of all its sides. Measured in units such as centimetres or metres.

The amount of flat surface a shape covers, measured in square units such as square metres. For a rectangle, multiply length by width.

The amount of space a solid occupies, measured in cubic units. For a box, multiply length by width by height.

Judging whether an answer makes sense in the context of the problem, checking size, units, and whether the result is possible. It is a key final step in problem solving.

Examining information carefully before accepting it, checking evidence, spotting assumptions, and considering alternative explanations or points of view.

A slant in data, a survey, or a report that pushes results in one direction, often because of how a sample was chosen or how a question was worded.

A smaller group selected from a larger population to represent it in a survey or study. A good sample is large enough and chosen without favouritism.

A method of collecting information by asking people questions. Question wording, who is asked, and how many respond all affect how trustworthy the results are.

The chance that something harmful or costly will happen, combined with how serious the consequence would be. Comparing risks helps people make informed decisions.

A choice made after gathering relevant facts, comparing options, and weighing costs, benefits, and risks rather than acting on impulse or guesswork.