Question

A car travelled 60 km to the north of Patna and then 90 km to the south from there. How far from Patna was the car finally?

Answer 1

Let the distance covered in the direction of north be positive and that in the direction of south be negative.

Distance travelled to the north of Patna = 60 km
Distance travelled to the south of Patna = -90 km
Total distance travelled by the car = 60 + (​-90)
= -30 km
The car was 30 km south of Patna.