A truck drove out of the city simultaneously in one direction at a speed of 90 km / h. and a passenger car with

A truck drove out of the city simultaneously in one direction at a speed of 90 km / h. and a passenger car with a speed of 115 km / h. How many kilometers will the truck lag behind the vehicle three hours after it starts moving? Try to find two ways to solve this problem. And one more solution in one action

1) 115 * 3 = 345 km – the car will pass
2) 90 * 3 = 270 km – the truck will pass
3) 345-270 = 75 km – the truck lagged behind the car
Answer: 75km