2. Calculation:1234× 2345-1233× 2346 (2006 Zhejiang Summer Camp Competition)

3, calculation: 7+77+777+7777+77777 (the second primary school "Hope Cup" fourth-grade training questions)

4. Calculation: 998+14 13+9989.

5. Calculation: 125×25× 128×39

6. Calculation: 2.005× 390+20.05× 4 1+200.5× 2 (item1in the fifth grade final exam of the third primary school)

7. Xiaohong and her mother are 28 years old this year, and her mother is five times as old as Xiaohong. Mom is 30 years old,

Xiaohong is old. (Differential multiple problems)

8. If a train with a length of 140m passes through a 400m-long tunnel at a speed of 60km, how many minutes will it take? (Train trip problem)

1, calculation: 9999×11+3333× 6667 (National Elementary School "Mathematical Olympic Star" Invitational Test /2006 Zhejiang Summer Camp Test)

2. Calculation:123456× 234567 × 234568×123455 (2005 summer camp test for primary schools in four provinces /2006 imaginary cup test).

3. Calculation: 471471471÷15715765438 (Laizhou, Shandong Province, 2000

4. Calculation: 2008× 20022002-2002× 20082008 (2005 Zhejiang Summer Camp /2002 National Olympiad Star Invitational Tournament for Primary School Students)

5. Calculation: 98989898× 9999999÷101÷165438.

1. Passenger cars and trucks leave from these two stations at the same time. Passenger cars travel 54 kilometers per hour and trucks travel 48 kilometers per hour. After the two cars meet, they go forward at the original speed and return immediately after arriving at the other station. When the two cars meet again, the bus travels 2 1.6 kilometers more than the truck. How many kilometers are the two stations apart?

Answer:122.4km.

2. The distance between Party A and Party B is 48km, one part is uphill and the other part is downhill. Someone rode a bike from place A to place B and went back the same way. It took 4 hours to get there, 12 minutes, and 3 hours and 48 minutes to come back. It is known that the speed of a bicycle when going uphill is 10 km. How many kilometers per hour does it go downhill?

Answer: downhill speed 15km.

There are all mountain roads between north and south towns. Some people walk 2 kilometers per hour up the mountain, 5 kilometers per hour down the mountain, 38 hours from Nanzhen to Beizhen, and 32 hours from Beizhen to Nanzhen. How far is it between the two towns? How many kilometers is it from Nanzhen to Beizhen?

Answer: 40 kilometers downhill and 60 kilometers uphill.

4. Party A travels12km per hour, and Party B travels 8km per hour. On a certain day, Party A went from the East Village to the West Village, and Party B went from the West Village to the East Village at the same time. Therefore, when Party B arrived in the East Village, Party A had already arrived in the West Village for five hours. Find out the distance between the east village and the west village.

The distance between Party A and Party B is the same, and the time for Party A is 5 hours less, so it takes t hours to form Party A..

free

1. 12t=8(t+5)

t= 10

So the distance = 120km.

Xiaoming and Xiao Fang are running by a pond. They started from the same point and walked in the same direction. Xiao Ming: 280 m/min; Small party: 220/ min. Eight minutes later, Xiao Ming caught up with Xiao Fang. How many meters is this pond in a week?

280*8-220*8=480

At this time, if Xiao Ming catches up the first time, it will be like this.

At this time, Xiao Ming ran again. ...

6. from a to b, someone rides a motorcycle 12 hours, and then rides a bike for 9 hours. When he returned, he rode his bike for 2 1 hour and then rode his motorcycle for 8 hours. How long does it take to get from a to b by motorcycle?

The motorcycle speed is xkm/h and the self-propelled speed is ykm/h.

2 1y+8x= 12x+9y

4x= 12y

x=3y

So the motorcycle * * * takes 12+9/3= 15 hours.

7. There are two trains, one with a length of102m and a speed of 20m per second; The length of the train is120m, and it runs at the speed of17m per second. Two cars are driving in the same direction. How many seconds does it take from the first train to catch up with the second train to the departure of the two cars?

Suppose it takes x seconds from the first train catching up with the second train to the departure of the two trains, and the equation is:

102+ 120+ 17x = 20x

x =74。

8. Someone walks at a speed of 2 meters per second. A train came behind, which took 10 seconds longer than him. As we all know, this train is 90 meters long. Find the speed of the train.

Assuming that the speed of the train is x meters per second, the equation is obtained.

10 x =90+2× 10

x = 1 1

9. At present, two trains run in the same direction at the same time. 12 seconds later, the express train overtook the local train. The express train runs18m per second, and the local train runs10m per second. If the tails of two trains are flush and driving in the same direction at the same time, the express train will overtake the local train after 9 seconds. Find the body length of two trains.

Express delivery length:18×12-10×12 = 96 (meters)

Length of local train: 18×9- 10×9=72 (m)

10, it takes 40 seconds for a train to cross a 440m bridge, and it takes 30 seconds to cross a 3 10/0m tunnel at the same speed. What is the speed and body length of this train?

(1) The train speed is: (440-310) ÷ (40-30) =13 (m/s).

(2) The body length is: 13×30-3 10=80 (m).

1 1, Xiaoying and Xiao Min take two stopwatches to measure the speed and length of the passing train. Xiaoying used her watch to record that the time that the train passed in front of her was 15 seconds. Xiao Min used another watch to record that it took him 20 seconds to cross the first telephone pole in front and the second telephone pole in the back. It is known that the distance between two poles is 100 meters. Can you help Xiaoying and Xiao Min calculate the total length and speed of the train?

(1) The train speed is:100 ÷ (20-15) × 60× 60 = 72,000 (m/h).

(2) The body length is 20× 15=300 (m).

12. It takes 40 seconds for a train to cross a 530-meter bridge and 30 seconds for a 380-meter cave at the same speed. What is the speed and body length of this train?

Let the train body be x meters long.

(530+X )÷40=(380+X )÷30

X=70

(530+X )÷40=600÷40= 15 (m/s)

13, two columns, one column length120m, speed 20m per second; The other train is160m long and runs at a speed of15m per second. The two cars are driving in opposite directions. How many seconds does it take from the front meeting to the back leaving?

The sum of the distances traveled by the two cars is exactly the sum of the distances of the two train conductors, so the time required for meeting the problem is: (120+160) ÷ (15+20) = 8 (seconds).

14, someone is walking at a speed of 2 meters per second. It took 10 seconds for a train to overtake him from behind. As we all know, the length of this train is 90 meters. Find the speed of the train.

The train passes by a person, and their distance difference is the conductor. Divide the distance difference (90 meters) by the passing time (10 second) to get the speed difference between the train and the people. This speed difference plus the walking speed of people is the speed of the train.

90÷10+2 = 9+2 =11(m)

15, express length182m, local length1034m, local speed18m. The two trains are parallel in the same direction. How long does it take for the express train to cross the local train when the rear of the express train meets the rear of the local train?

1034 ÷ (20-18) = 91(seconds)

16, express length182m, local length1034m, local speed18m per second. The two cars are parallel in the same direction. How many seconds can an express train pass through the local train when the heads of the two cars are aligned?

182 ÷ (20-18) = 91(seconds)

17. A person is running along the railway at a speed of 120 meters per minute. A 288-meter-long train came from the opposite side. It took him 8 seconds to find the speed of the train.

288 \8- 120 \60 = 36-2 = 34 (m/s)

18. A train is 600 meters long. It passes through a 200-meter-long tunnel at a speed of 10 meter per second. How long does it take from the front to the rear?

(600+200) 10 = 80 (seconds)

19, Xiaoming rode his bike from a to b at 8: 00 in the morning at a speed of12km, and Xiao Qiang rode his bike from b to a at 8: 40 in the morning at a speed of16km. They meet at the midpoint of A and B. What is the distance between A and B?

They met at the midpoint of the distance between the two places, but Xiao Ming walked 40 minutes longer than Xiao Qiang. If they set out at the same time, when they met, Xiao Ming walked less than Xiao Qiang 12÷60×40=8 (km), that is to say, when Xiao Qiang set out, Xiao Ming had already walked 8 km, and they met at 8: 40, because Xiao Ming walked less every hour than Xiao Qiang. Explain that the meeting time of two people is 8÷4=2 (hours), then the distance between A and B is 8+( 12+ 16) × 2 = 64 (kilometers).

20. Village A and Village B are 3550 meters apart. Xiao Wei walked from village a to village b. Five minutes after the departure, Xiao Qiang walked from village B to village A by bike. 10 minutes later, he met Xiao Wei. Xiao Qiang rides bicycles more than Xiao Wei walks per minute160m. How many meters does Xiao Wei walk every minute?

If Xiao Qiang walks less 160m per minute and his walking speed is the same as that of Xiao Wei, then Xiao Qiang walks less160× 10 =1600 (meters) within10 minutes. The walking distance between Xiao Wei (5+ 10) and Xiao Qiang (10) is 3550- 1600 = 1950 (meters), so the walking distance of Xiao Wei is 1950 \( 5).

2 1. The bus leaves from Dongcheng, and the truck leaves from Xicheng at the same time, face to face. Buses travel 44 kilometers per hour and trucks travel 36 kilometers per hour. The bus to the west side is two hours earlier than the truck to the east side. How many hours did the two cars meet on the road after they set off?

When the bus arrives in the west city, the distance between the truck and the east city is 2×36=72 (km), while the hourly journey of the truck is 44-36 = 8 (km) less than that of the bus, and the time for the bus to travel to and from the east and west city is 72÷8=9 (hours), so the distance between the east and west city is 44×9=396 (km), so two cars are needed from the departure to the meeting. 396 ÷ (44+36) = 4.95 (hours)

22. Party A and Party B set off from Beijing on the same day and rode along the same road to Guangzhou. Party A travels 65,438+000 kilometers every day, and Party B travels 70 kilometers on the first day, and then travels 3 kilometers more than the previous day until they catch up with Party A. How many days after Party B leaves?

At first, Otsuichi Skywalker was less than A 100-70 = 30 (km). Later, B walked 3 km more every day, and it took 30÷3= 10 (day) to reach the same speed as A, that is, on the first 10 day, the distance between A and B widened day by day, and the 60th.

23. The distance between A and B is 10 km. Both the express train and the local train go from A to B. When the express train leaves, the local train has already traveled 1.5 km. When the express train arrives at B, the distance between the local train and B is still 1 km, so how many kilometers away from B does the express train catch up with the local train?

The local train traveled 1.5km before the express left, but when the express arrived at B, the local train distance B was still 1km, that is, in the time of the express 10km, the distance more than the local train was 1.5+ 1 = 2.5(km The speed of the express train 1km is 2.5÷ 10=0.25 (km) more than that of the local train.

24. Class A and Class B have a cross-country marching competition. Class A runs half the distance at a speed of 4.5 km/h and the other half at a speed of 5.5 km/h; During the competition, Class B travels at a speed of 4.5 km/h half the time and at a speed of 5.5 km/h the other half. Q: Who will win Class A or Class B?

The longer you walk, the shorter it takes. The fast walking distance of Class A is the same as the slow walking distance, and the fast walking distance of Class B is longer than the slow walking distance, so Class B wins.

25. It takes three days for the boat to travel from City A to City B, and four days from City B to City A. How many days does it take to put an unpowered raft from City A to City B?

It takes 3 days for a ship to go downstream and 4 days for a ship to go upstream, which means that the ship is traveling in still water for 4-3 = 1 (days), which is equal to 3+4 = 7 (days) of the current, that is, the speed of the ship is 7 times of the current. Therefore, the three-day trip of the ship is equal to the 3+3× 7 = 24 (days) trip of the current, that is, it takes 24 days for the raft to drift from city A to city B.

26. Xiaohong and Xiao Qiang started from home at the same time and walked in opposite directions. Xiaohong walks 52 meters per minute and Xiao Qiang walks 70 meters per minute. They meet on the way. If Xiaohong leaves four minutes early and the speed remains the same, and Xiao Qiang walks 90 meters every minute, then the two will still meet at point A. How many meters away is Xiaohong from Xiao Qiang's home?

Because Xiaohong's speed and meeting place remain the same, Xiaohong's time from departure to meeting is the same twice. In other words, Xiao Qiang walked four points less than the first time. pass by

(70× 4) ÷ (90-70) = 14 (minutes)

It can be seen that Xiao Qiang left for the second time 14, and it is inferred that he left for the first time 18, and their homes were separated.

(52+70) × 18 = 2 196 (m)。

27. Xiaoming and Xiaojun set out from A and B respectively at the same time and went in opposite directions. If two people go at the original speed, meet at 4 o'clock; If both are faster than the original speed 1 km/h, meet at 3 o'clock. How many kilometers is it between A and B?

Walking every hour 1 km, two people walk 6 km at 3 o'clock, which is equivalent to the distance that two people walk at the original speed 1. So the distance between A and B is 6× 4 = 24 (km).

28. Party A and Party B practice running along the 400-meter circular track, and both sides run in opposite directions from the same place on the track at the same time. After the encounter, the speed of A increased by 2m/s, and the speed of B decreased by 2m/s, so that they all returned to their original places within 24 seconds. Find the original velocity of a.

Because the speed of A and B is the same before and after meeting, it takes 24 seconds to run a circle together after meeting, so it takes 24 seconds to run a circle together before meeting, which is 24 seconds to meet.

Suppose A originally ran x meters per second, and then ran (x+2) meters per second after meeting. Because A ran back and forth for 24 seconds and * * ran 400 meters, there is 24x+24 (x+2) = 400, and the solution is x=7, 1/3 meters.

29. Two cars A and B are driving in opposite directions from two stops A and B on the expressway respectively. It is known that the speed of car A is 1.5 times that of car B, and the time for car A and car B to arrive at station C is 5: 00 and 16:00 respectively. What time did the two cars meet?

It takes 16-5 = 1 1 (hours) for a car to get to station c, and1/when the second car is driving, it takes 1 1 ò

30. An express train goes in the opposite direction to a local train. The length of the express train is 280 meters and the length of the local train is 385 meters. The time for people sitting on the express train to see the slow train pass is 1 1 sec, so how many seconds does it take for people sitting on the slow train to see the express train pass?

The speed at which people on the express train see the local train is the same as the speed at which people on the local train see the express train, so the length ratio of the two cars is equal to the time ratio at which the two cars pass by, so the time required is 1 1.

3 1, Party A and Party B practice running. If Party A lets Party B run 10 meter first, Party A can catch up with Party B after running for 5 seconds. If B runs 2 seconds ahead of A, A can catch up with B in 4 seconds. Q: How many meters do two people run per second?

The speed difference between Party A and Party B is 10/5=2.

The speed ratio is (4+2): 4 = 6: 4.

So A runs 6 meters per second and B runs 4 meters per second.

32. A hare escaped 80 steps before the hounds caught up with it. Hunting dogs only need to run three steps out of eight, and rabbits can run nine steps out of four. How many steps does a hound have to run to catch up with a hare?

The distance of dog running 12 step is equal to the distance of rabbit running 32 steps, and the time of dog running 12 step is equal to the time of rabbit running 27 steps. Therefore, every time the rabbit runs 27 steps, the dog catches up with 5 steps (rabbit step), and the dog needs to run [27× (80 ÷ 5)+80] ÷ 8× 3 = 192 (step) to catch up with 80 steps (rabbit step).

33. Two people, A and B, were walking along the railway at the same speed when a train came. The whole train took 18 seconds to pass through A, and 15 seconds to pass through B two minutes later. Q:

(1) What is the speed of the train?

(2) After the train passes by B, how long will it take for A and B to meet?

(1) If the train speed is a m/s and the pedestrian speed is b m/s, the train speed is 1 1 times the pedestrian speed;

(2) From the tail of the train passing through A to the tail of the train passing through B, the train travels 135 seconds. It takes 1350×11=1485 (seconds) for one person to walk this distance, so two people walk the rest distance because A has already walked135 seconds.

34. There are two docks A and B along the Yangtze River. It is known that passenger ships sail 500 kilometers from A to B and 400 kilometers from B to A every day. If it takes 18 days for a passenger ship to sail five times between Pier A and Pier B, what is the distance between the two piers?

800 kilometers

35. Bus length 190 meters, truck length 240 meters. The two cars are traveling at a speed of 20 meters per second and 23 meters per second respectively. How many seconds does it take to meet from front to back on the double-track railway?

10 second.