John draws a map by taking a scale of 2 cm as 30 km. If the distance between cities A and B on his map is 7 cm, and distance between C and D is 13 cm, then what is the difference between the actual distances of the cities AB and CD?

Distance between cities A and B on John’s map = 7 cm Let the actual distance between the two cities be d km The scale used in the map is 2 cm = 30 km Therefore, by setting the proportion, we obtain the actual distance between the cities AB as 105 km. The distance between cities C and D on John’s map is 13 cm. Let the actual distance between the two cities be d km. The scale used in the map is 2 cm = 30 km. Therefore, by setting the proportion, we obtain the actual distance between the cities CD as 195 km. Hence, the difference between both the cities AB and CD is 90 km. Option (4) is correct.