How long does it take for a car to travel m kilometers per hour and t hours to reach its destination? If it travels n kilometers more per hour, how long does it take for the car to complete this section of the road?

How long does it take for a car to travel m kilometers per hour and t hours to reach its destination? If it travels n kilometers more per hour, how long does it take for the car to complete this section of the road?

Trains travel 120 kilometers per hour, and cars 80 kilometers per hour. The m-hour train travel is more than N-hour car travel______ Kilometers

120 × M-80 × n = 120m-80n (km); a: the train runs 120m-80n km more than the car for M hours; so the answer is: 120m-80n

The car goes from a to B. It is planned to travel 54 kilometers per hour and 3.5 hours to B. actually, it travels 9 kilometers more per hour. How many hours will it arrive?
It's urgent

54 × 3.5 ÷ (54 + 9) = 2.5 hours

A. The distance between B and B is 30 kilometers. A and B start from a respectively. A starts for 1 hour, and then B starts at a speed of 2 kilometers more than a per hour
As a result, both of them arrived at B at the same time. If a set out 0.5 hours earlier, then when B caught up with a, they would be thousands of meters away from B

Let a's speed be x km / h and B take t hours to get to B
X(t+1)=(X+2)t=30
Solution
X=2t
Suppose that a starts 0.5 hours early, and when B catches up with a, it takes y hours
X(Y+0.5)=(X+2)Y
Solution
X=4y
so
t=2y
So they're 15 kilometers away from B