Map scales can be represented as
(a) Verbal or statement scale—i.e. the scale is stated in words as 1 cm = 5 km or 1 cm to 5 km. It means 1 cm on the map is equal to 5 km on the ground.
(b) Representative fractions — In this system, the numerator expresses the distance on the map, and the denominator represents the actual distance on the ground. Both should have the same units i.e. 1 cm on the map represents 50,000 cm on the ground.
R.F = distance on map cm / distance or ground cm