How are the scales stated in the statement, representative fraction and graphic scale methods?

There are three ways in which the scale can be shown on a map.

By a statement — In the statement method, the scale is expressed in words such as two centimetres is to five kilometres or 2 cm : 5 km. In this statement, 2 cm is the map distance and 5 km is the ground distance. This is a quick and easy method of using the scale to measure distances.

By a representative fraction — In the representative fraction (R.F.) method, the scale is expressed in numerical fraction. In this method, the ratio between the map distance and the ground distance is given as a fraction, whose numerator is always 1. The numerator represents the map distance and the denominator represents the ground distance. Thus,
R.F. = $\dfrac{\text{map distance}}{\text{ground distance}}$

It can also be written as map distance : ground distance.

For example, $\dfrac{1}{1,00,000}$ or 1 : 1,00,000

By a graphic or linear scale — In the graphic or linear scale method, the map distance is shown using a straight line. The length of the line depends on the size of the map. It is usually between 12 cm and 20 cm. This line is divided into parts known as primary divisions. Usually the first primary division on the left is further sub-divided into smaller parts known as secondary divisions. The starting or zero point of the linear scale should be after the first primary division from the left. The primary divisions are to the right of zero, and the secondary divisions are to the left of zero. The linear scale is useful to measure the distance directly from the map.