Elementary school equation application problem itinerary problem Meet, journey. The more the better

Elementary school equation application problem itinerary problem Meet, journey. The more the better

1. Party A and Party B set out at the same time from two places with a distance of 30 kilometers. Party A walked 6 kilometers per hour and Party B walked 4 kilometers per hour. Question: how many hours will they meet?
2. Xiaoli's home is 3 kilometers away from school. At 6 o'clock in the evening, Xiaoli comes home from school and her mother goes to school from home. Her mother rides 175 meters per minute and Xiaoli walks 75 meters per minute. When will they meet?
3. Wang Qiang drives from Beijing to Tianjin, 60 kilometers per hour. Li Ming drives from Tianjin to Beijing, 50 kilometers per hour. They set out at the same time. After 40 minutes, they met on the way. Question: how many kilometers is the distance between Beijing and Tianjin?
4. The distance between Party A and Party B is 150 km. Two cars drive from place a to place B at the same time. The speed of the first car is 40 km / h, and the speed of the second car is 35 km / h. The first car returns to place a immediately after arriving at place B, and meets the second car on the way. Q: how long did it take from their departure to their meeting?
5. Car a and car B travel from city a and city B respectively. Car a travels 70 kilometers per hour and car B 65 kilometers per hour. The distance between the two cars' meeting point and the midpoint of the whole journey is 20 kilometers. How long is the whole journey
1. My sister's walking speed is 75 m / min, and my sister's walking speed is 65 m / min. after 20 minutes of my sister's departure, my sister set out to catch up with my sister. Q: how many minutes can I catch up with her?
2. Xiao Zhang and Xiao Wang start to walk from village a and village B at the same time. One hour and 15 minutes later, Xiao Zhang walks half the distance between village a and village B, which is more than 0.75 km. At this time, he meets Xiao Wang. Xiao Wang's speed is 3.7 km / h, so what's Xiao Zhang's speed? (unit: km / h)
3. Xiao Zhang planned to walk 50 meters every minute from home to the park. In order to arrive 10 minutes earlier, he quickened his pace and walked 75 meters every minute. How far is it from home to the park?
4. A bicycle is moving at a fixed speed in front of it, and there is a car to catch up with. If the speed is 30 km / h, it will take 1 hour to catch up; if the speed is 35 km / h, it will take 40 minutes to catch up. What is the speed of the bicycle?
5. Xiao Zhang walks 5 kilometers an hour from place a to place B, and Xiao Wang walks 4 kilometers an hour from place B to place A. they set out at the same time, and then meet one kilometer away from the midpoint of place a and place B to find the distance between the two places
1. The length of train a is 210 meters, 25 meters per second, and that of train B is 20 meters per second. The two trains are running in the same direction. Train a has overtaken train B for more than 80 seconds. The length of train B is calculated
2. It takes 100 seconds for a train to pass the 340 meter bridge. It takes 72 seconds for a train to pass the 144 meter bridge at the same speed. Find the speed and length of the train
3. The two cars are facing each other. The bus is 168 meters long, 23 meters per second, and the truck is 288 meters long, 15 meters per second. Q: how long does it take for the two cars to meet and leave?
4. Train a runs 18 meters per second, and train B runs 12 meters per second. If two trains go hand in hand, train a will exceed train B in 40 seconds. If two trains go hand in hand, train a will exceed train B in 30 seconds
5. Lao Li took a walk along the railway. He walked 60 meters per minute. A 300 meter long train came to him. He met the front of the train and separated from the back of the train for 20 seconds. He asked for the speed of the train
1. A, B and c run a 200 meter race. When a reaches the finish line, B is 20 meters away from the finish line, and C is 25 meters away from the finish line. If the speed of a, B and C does not change, how many meters will C be away from the finish line when B reaches the finish line?
2. A, B, C three people walk, a walk 60 meters per minute, B walk 50 meters per minute, C walk 40 meters per minute. A from a, B and C start from B at the same time, facing each other, a and B meet, after 15 minutes and meet with C, to find the distance between a and B
3. A, B and C are three stations on the same road. The distance from station B to station a and C is equal. Xiaoqiang and Xiaoming start from station a and C respectively. Xiaoqiang meets Xiaoming 100 meters after station B, and then they continue to move forward. Xiaoqiang goes back to station C, and overtakes Xiaoming 300 meters after station B. Q: what's the distance between station a and station B?
4. On the circular track with a circumference of 400 meters, there are two points a and B 100 meters apart. A and B run from two points a and B at the same time. When they meet, B turns around and runs in the same direction as a. when a runs to a, B just runs to B. if the speed and direction of a and B do not change in the future, how many meters did a run when catching up with B?
5. On a highway, there is a cyclist and a pedestrian. The speed of the cyclist is three times that of the pedestrian. Every six minutes, a bus overtakes the pedestrian, and every ten minutes, a bus overtakes the cyclist. If the time interval at the bus departure station remains the same, the bus will leave at the same time, How many minutes does a bus leave? 1. The speed of a ship in still water is 15 kilometers per hour. It takes 8 hours for it to go from the upstream to the downstream. The water speed is 3 kilometers per hour. How long does it take for it to return from the upstream to the downstream?
2. The waterway between port a and port B is 208 km long. A ship sails from port a to port B, arrives 8 hours downstream, returns to port a from port B, and arrives 13 hours upstream. The speed of the ship in still water and the current speed are calculated

Travel problem application problem (to list equations!)
(1) The distance between stations a and B is 240 km. A bus runs 48 km per hour from station a, and a car runs 72 km per hour from station B. one hour after the car runs from station B, the bus runs from station a, and the two cars face each other. A few hours later, the two cars meet?
(2) A tractor must go to pick up the goods. It's 30 kilometers per hour. After 30 minutes of departure, there is something at home to send a car to catch up with the tractor at the speed of 50 km / h. how long does it take for the car to catch up with the tractor?

(1) The distance between stations a and B is 240 km. A bus runs 48 km per hour from station a, and a car runs 72 km per hour from station B. one hour after the car runs from station B, the bus runs from station a, and the two cars face each other. A few hours later, the two cars meet?
Let two cars meet in X hours
72x1+(72+48)x=240
120x=168
x=1.4
(2) A tractor must go to pick up the goods. It's 30 kilometers per hour. After 30 minutes of departure, there is something at home to send a car to catch up with the tractor at the speed of 50 km / h. how long does it take for the car to catch up with the tractor?
Let the car catch up with the tractor in X hours
50x=30x+30x1/2
20x=15
x=0.75

Plus and minus exercises
80 plus and minus or plus and minus mixed operation
80
Oh, my God. I just want to practice, so I'm looking for a question. I'm dizzy

(1)23+(-73) (2)(-84)+(-49) (3)7+(-2.04) (4)4.23+(-7.57) (5)(-7/3)+(-7/6) (6)9/4+(-3/2) (7)3.75+(2.25)+5/4 (8)-3.75+(+5/4)+(-1.5) 1)(-17/4)+(-10/3)+(+13/3)+(11/3) (2)(-1.8)+(+0.2)+(-1.7)+(0.1)+(+1.8)+(...

On the addition of positive and negative numbers
1+（-2）+3+（-4）+5+（-6）+7+（-8）+…… +99+（-100）=?
To simplify the process of calculation

1+(-2)=-1
3+(-4)=-1.
-1*50=-50

Exercises on addition of positive and negative numbers
One positive and one negative,

10-12=-2
8-15=-7
44-80=-36
12-100=-88
-2+10=8
-15+36=21
-9+44=35

How to solve some positive and negative addition problems

-1+（+2）
+5+（-3）
+7+（-4）

Ten plus and minus problems of positive and negative numbers
Example: 5 + (- 3)
Trouble. Give me an answer before you offer it

3+(-2)=1
4-(-2)=6
13+(-6)=7
25-(-8)=33
60+(-80)=-20
22-(-20)=42
(-12)+20=8
(-33)-18=-51
(-7)+6=-1
(-2)-8=-10

How to set up the positive and negative addition and subtraction

That's what I said,
In fact, the minus sign of a negative number is regarded as a minus sign, which may be easier to understand
The law of addition: two numbers are added, and the same sign (that is, both positive numbers or negative numbers) is added. Take the sign, and put the
For example: - 2 + (- 5) = - (2 + 5) = - 7
The sign of the number with the largest absolute value is taken and the absolute value is subtracted
For example: 2 + (- 7) = - (7-2) = - 5
Any number plus 0 is still equal to that number. For example: - 4 + 0 = - 4
Subtraction rule: subtracting a number is equal to adding the opposite number of the number. For example: 4 - (- 2) = 4 + 2 = 6
Multiplication rule: if there are even negative numbers, take the positive sign and multiply the absolute value. For example: - 2 * (- 5) = + (2 * 5) = 10. If there are odd negative numbers, take the negative sign and multiply the absolute value. For example: 2 * (- 5) = - (2 * 5) = - 10
Any number multiplied by 0 is still 0
Division rule: dividing by a number is equal to multiplying the reciprocal of the number. For example: 2 divided by 5 = 2 * (1 / 5) = 2 / 5
Opposite number: two numbers with different symbols are opposite to each other, such as 4 and - 4
Absolute value: just remove the sign. For example, the absolute value of - 4 is written as: | - 4 | = 4

Application of positive and negative numbers
Question type:
For example, mountain climbing, the surface temperature... Every rise of... Meters or kilometers, the temperature will drop... To find the temperature of... Meters or kilometers of the top of the mountain

For example: if climbing up a mountain is + then climbing up 2m is () and climbing down 2m is () very simple, climbing up 2m is + and adding a positive sign (or writing 2m directly) in front of 2m; positive and negative are quantities in the opposite sense, the same, up

Help out a few junior one positive and negative application problems
It's a kind of roundabout,

1. The weight of 10 students was measured by physical examination. Based on 50kg, the number of excess was positive and the number of deficiency was negative. The results were as follows (unit: kg): 2,3, - 7.5, - 3,5, - 8,3.5,4.5,8, - 1.5
What is the total weight and average weight of the 10 students?
2. The meteorological observation data of a sounding balloon show that the air temperature decreases about 6 ℃ when the altitude increases by 1 km. If the ground temperature of the area is 21 ℃, and the temperature of a place in the upper air is - 39 ℃, how many km is the altitude here?
3. One day, Xiaoming and Dongdong used the temperature difference to measure the height of the mountain peak. Dongdong measured the temperature at the foot of the mountain at 4 ℃. Xiaoming measured the temperature at the top of the mountain at 2 ℃. It is known that when the height of the area increases by 100 meters, the temperature drops by 0.8 ℃. How high is the mountain peak?
===I hope my answer will help you,