The scale of a map is 1 cm : 12 km. if two cities are 1.5 cm apart on the map, what is the actual distance between the cities

The easiest way to do this is to multiply 12km by 1.5. That will give you one and half the value of 12, which will represent the actual distance between the two cities.

12 * 1.5 = 18

The two cities are actually 18 kilometers away from each other.