Key terms & definitions

The arithmetic difference between two percentages. An increase from 20% to 25% is an increase of 5 percentage points.

The difference between two percentages, found by subtracting one percentage from the other.

A difference between two percentages, found by subtracting one percentage from the other.

The difference between two percentages, found by subtracting the earlier percentage from the later one.

The amount of product actually obtained expressed as a percentage of the maximum theoretical amount.

A value marking a particular percentage position in ordered data. Approximately 90% of values lie at or below the 90th percentile.

A value below which a stated percentage of the reference population falls.

A value below which a stated percentage of a reference population falls. For example, the 25th percentile for mass is the mass below which approximately 25% of the comparison group falls.

A value below which approximately a specified percentage of ordered data lies; for example, the 90th percentile marks approximately 90% of the data.

A value below which a stated percentage of measurements in a population falls. For example, about 5% fall below the 5th percentile.

A graph that compares a child's measurement at a particular age with measurements from a reference population.

A line joining measurements that occupy the same relative position in the reference population at different ages.

The way a person understands or interprets a place, condition or risk, influenced by their experiences, knowledge and values.

Recognising and interpreting what is experienced, drawing on previous experience.

The process of interpreting information received through the senses.

An increase in the apparent intensity or prominence of a stimulus because it relates to a person's needs or desires.

A readiness to perceive certain things rather than others, influenced by experience, expectations, needs and feelings.

The downward movement of water through pores and cracks into rock beneath the soil.

A firing mechanism in which a hammer strikes a small explosive cap to ignite the gunpowder charge.

Gorbachev’s policy of restructuring the Soviet economy to improve its performance.

An ideal object that absorbs all radiation incident on it, reflecting and transmitting none.

A whole number made by cubing an integer, such as $125=5^3$. Perfect cubes help when estimating cube roots.

An inelastic collision in which the objects join together and move with one common velocity afterwards.

An integer that can be written as $a^n$, where $a$ is an integer and $n$ is an integer greater than $1$; for example, .

An expression such as $(x+p)^2$ obtained by multiplying the same linear expression by itself.

Effectiveness when a contraceptive is used correctly and consistently every time.

Contraceptive effectiveness when a method is used correctly and consistently.

How well a method prevents pregnancy when it is used correctly every time.

A line of small cuts separated by uncut material, which can make paper or board easier to tear or fold.

The execution of an action, or the ability to achieve a task effectively and efficiently.