There are three ways to show proportions on a map:
$(1)$ Statement method or statement $(2)$ Numerical method or representative fraction $(3)$ Graphical scale
$(1)$ Statement method or statement of measure:
In this method all the details of the measurement are represented by word or statement.
Such as $1 \ cm: 10 \ km$ i.e. map but a distance of $1 \ cm$ shows a distance of $10 \ km$ on the surface of the earth.
$(2)$ Numerical method or representative fraction:
In this method, units of measure of length or distance are not written with the number indicating the measure. Distances are represented only by numeric numbers or fractions.
For example, if the statement scale is $1 \ cm: 10 \ km,$ it is written as $1 / 10,00,000$ or $1 / 10,00,000$
$(3)$ Graphic scale or linear scale:
In this method, a measuring bar that is directly measurable or readable on the ground is drawn in one part of the map. The scale represented by drawing in this way is called graphical scale.