The actual distance between the airport and the railway station is 84 kilometers. How many centimeters should be drawn on a map with a scale of 1:300000? How many centimeters should be drawn on a map with a scale of 1:6000000 How many centimeters should be drawn on the wall?

The actual distance between the airport and the railway station is 84 kilometers. How many centimeters should be drawn on a map with a scale of 1:300000? How many centimeters should be drawn on a map with a scale of 1:6000000 How many centimeters should be drawn on the wall?

Forget the ceiling,
On a map with a scale of 1:300000:
84 × 1 / 300000 = 0.00028 (km) = 28 (CM)
On a map with a scale of 1:6000000:
84 × 1 / 6000000 = 0.000014 (km) = 1.4 (CM)

The distance between the two stations is 300 km. An express train starts from station a with a speed of 60 km / h, and a slow train starts from station B with a speed of 40 km / h
Such as the title
(1) Two cars start at the same time, go opposite each other, and meet in a few hours?
(2) The express train starts for 15 minutes. The two trains are facing each other. How many hours after the express train leaves, the two trains meet?
(3) The two trains leave in the same direction at the same time. How long does the local train leave before the express train catches up with the local train?
Solve by equation
It's going to be a linear equation of one variable

(1) Let's meet in X hours
（60+40）X=300
X=3
(2) Let's meet in X hours
(60 + 40) (x-1 / 4) = 300-60 times 1 / 4
X=3.1
(3) After setting x hours
（60-40）X=300
X=15
This kind of thing uses a linear equation of one variable

The distance between the two stations is 300 km. The speed of an express train from station a is 60 km / h, and that of an idle train from station B is 40 km / h
1. If the express train runs for 15 minutes first, and the two trains are facing each other, how many hours later will the two trains meet?
2. If the local train drives for 30 minutes first, the two trains are facing each other and the local train is ahead, how long can the express train catch up with the local train after departure? How many kilometers has the local train traveled at this time?

1. Let's meet after n hours. According to the meaning of the question, we get the equation: (60 + 40) × n = 300-60 × 15 / 60
The solution is n = 2.85
The local train will meet after 2.85 hours
2. Suppose that the fast train can catch up with the slow train in M hours after departure. According to the meaning of the question, the equation is as follows: (60-40) × M = 300 + 40 × 30 / 60
The solution is m = 16
At this time, the local train runs: 40 × (30 / 60 + 16) = 660 (km)

The distance between station AB and station a is 300 km. The speed of an express train from station a is 60 km per hour, and that of an idle train from station B is 40 km per hour
Question: how long does the slow train run in the same direction after 30 minutes of driving? How long does the slow train catch up with the fast train in front of it? How many kilometers does the slow train travel at this time
It's an equation

8751476,
Set the express train to catch up with the local train after X hours
60X－40X＝40×30/60
20X＝20
X＝1
At this time, the local train runs:
40 × (30 / 60 + 1) = 40 × 1.5 = 60 (km)