Step-by-step explanation:
Given that,
There are two cars say A and B. Both are approaching each other moving towards westward.
Speed of car A,

Speed of car B,
We need to find the velocity of the first car relative to (in the reference frame of) the second car. As both are moving in same direction, there relative velocity is given by :


v' = 19 km/h
So, the velocity of car A with respect to car B is 19 km/hr. Hence, this is the required solution.