2. Some blocks have more than 50 blocks and less than 70 blocks, every 7 blocks 1 block, every 9 blocks 1 block, or 1 block. How many blocks are there?
3.6 Potted flowers should be arranged in 4 rows with 3 pots in each row. How should we arrange them?
Four people from Class 4.4 (1) participated in the 4X50 relay race. How many different arrangements are there?
5. Can you choose five numbers from the picture on the right so that their sum is 60? Why? 15 25 35
25 15 5
5 25 45
6.5 The sum of consecutive even numbers is 240. What are five even numbers?
7. 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?
1、 186576× 1999 1 1- 1999 12× 186575=( )。
2. Find the rules for filling numbers: ① 1 1, 12, 14,18,26 ().
② 1,2,2,4,8,32( )。
3, six consecutive natural numbers, the sum of the first three numbers is 60, then the sum of the last three numbers is ().
4. The sum of numbers A, B and C is 1 16, and the number A divided by the number B and the number C divided by the number A are all quotient 2 and 1, so the number B is ().
A store stipulates that three empty soda bottles can be exchanged for one soda bottle. Xiao Ming bought eight bottles of soda, and after drinking, he exchanged the empty soda bottles for soda. He can drink 100 bottles of soda as soon as he gets up.
7. The dividend is 3320, the quotient is 150, the remainder is 20 and the divisor is ().
First, fill in the numbers according to the law.
1)64,48,40,36,34,( )
2)8, 15, 10, 13, 12, 1 1,( )
3) 1、4、5、8、9、( )、 13、( )、( )
4)2、4、5、 10、 1 1、( )、( )
5)5,9, 13, 17,2 1,( ),( )
Second, arithmetic progression.
1. In arithmetic progression, 9 12, 2 1, 30, 39, 48, …
2. Find the sum of all integers between 1 and 100 that are not divisible by 5 or 9.
3. Divide 2 10 by the sum of seven natural numbers, so that after the seven numbers are arranged in a row from small to large, the difference between two adjacent numbers is 5. So, what is the number of 1 and the sixth number?
4. Group all odd numbers starting from 1, where the first number of each group is equal to the number of all numbers in the group, such as (1), (3,5,7), (9,0/1,13,660.
5. Arrange the natural numbers as follows.
1 2 6 7 15 16 …
3 5 8 14 17 …
4 9 13 18 …
10 12 …
1 1 …
…
In this arrangement, the numbers are arranged in the second row 1 column and the third row 13 column. Q: What is the rank of 1993?
Third, the average problem.
1. The average number of 9 known is 72. After removing a number, the average of the remaining numbers is 78, and the removed number is _ _ _ _ _.
There are 40 students in a class, and two students missed the mid-term math exam for some reason. At this time, the average score of the class is 89, and the students who are absent from the exam each get 99 points. The average score of the senior high school entrance examination in this class is _ _ _ _ _ _ _ _.
In the first five months of this year, Xiaoming saved money in 4.2 yuan on average every month. Since June, he has saved 6 yuan every month. Since which month, Xiaoming has saved more money than 5 yuan on average?
4.a, B, C, D, remove one number at a time and average the remaining three numbers. This is calculated four times, and the following four numbers are obtained.
23, 26, 30, 33
What is the average of a, b, c and D 4?
Remove one of the five numbers A, B, C and D4 at a time, and average the remaining three numbers, so that the following four numbers 23, 26, 30 and 33 are counted four times, and the sum of A, B, C and D4 is.
Fourth, simple operations of addition, subtraction, multiplication and division
1) 100-98+96-94+92-90+……+8-6+4-2=( )
2) 1976+ 1977+……2000- 1975- 1976-……- 1999=( )
3)26×99 =( )
4)67× 12+67×35+67×52+67=( )
5)( 14+28+39)×(28+39+ 15)-( 14+28+39+ 15)×(28+39)
Five, the number of arrays.
1, △, □, and zero respectively represent three different numbers;
△+△+△=〇+〇; 〇+〇+〇+〇=□+□+□; △+〇+〇+□=60
Question: △ =△ =□ =
2. Fill in nine consecutive natural numbers in the nine spaces of three rows and three columns, so that the sum of the three numbers in each row and each vertical column is equal to 60.
3. Fill nine consecutive odd numbers starting from 1 into nine spaces in three rows and three columns, so that the sum of three numbers in each row, each column and two diagonal lines is equal.
4 Make a third-order magic square with 9 numbers from 1 to 9, and write all possible results. The so-called magic square refers to filling different numbers in each square of the square grid table, so that the sum of numbers on each row, column and two diagonal lines is equal; Order refers to the number of squares contained in each row and column.
Sixth, the problem of sum and difference times.
1. There are 340 peach trees and apricot trees planted in the orchard, of which the number of peach trees is 20 times more than that of apricot trees. How many trees have been planted?
2. Rectangular, 30cm in circumference, twice as long and wide. Find the area of this rectangle.
3.A and B are two numbers. If A plus 320 equals B, if B plus 460 equals 3 times A, what are these two numbers?
There are two pieces of cloth with the same length. The first piece sells for 25 meters, the second piece sells for 14 meters, and the remaining piece of cloth is twice as long as the first piece. How many meters is each piece of cloth?
There are 150 peach and pear trees in the orchard. There are 20 more peach trees than pear trees. How many fruit trees are there?
6. Two barrels of oil A and B weigh 30 kilograms. If 6 kilograms of oil in barrel A is poured into barrel B, the weight of the two barrels of oil is the same. How much oil do they have?
Seven, the age problem
1. The two brothers are 30 years old this year. When my brother and brother are the same age now, my brother is exactly half his age. How old is my brother this year?
The mother and daughter are 64 years old, and the daughter is three years older than her mother. How old are the mother and daughter?
My brother is older than Xiaoli this year 12 years old. Eight years ago, my brother was four times older than Xiaoli. How old are they this year?
Grandpa is 72 years old and grandson 12 years old. A few years later, grandpa was five times as old as his grandson. A few years ago, my grandfather was 13 times older than my grandson.
Eight. Hypothetical problem
1.42 students participated in tree planting, with an average of 3 trees planted by boys and 2 trees planted by girls, with 56 more trees planted by boys than girls. How many boys and girls are there?
2. A primary school held a math contest with *** 15 questions. He gets 8 points for every right question and 4 points for every wrong question. Xiaoming got 72 points in the exam. How many questions did he get right?
There are 25 questions in a test paper. Answer one question correctly and get 4 points. Answer correctly or not, get 1 point. A classmate will get 60 points. He answered several questions correctly.
4. Xiaohua answers math judgment questions, giving 4 points for a correct answer and 4 points for a wrong answer. She answered 20 true and false questions and got only 56 points. She answered several questions wrong.
5. Yucai Primary School held a math contest in the fifth grade. There are *** 10 questions. She gets 8 points for each correct question, and 5 points for wrong questions. Zhang Xiaoling finally got 4 1 point. How many questions did she answer correctly?
Two toy electric cars A and B run from both ends of the track at the same time. A car travels 5 cm per second, B car travels 1 cm in the first second, 2 cm in the second, and 3-,so when the two cars meet, the distance is the same, so how many centimeters is the track?
1. Party A, Party B and Party C plant trees in two plots A and B respectively, with 900 trees in plot A and 0/250 trees in plot B. It is known that Party A, Party B and Party C can plant 24, 30 and 32 trees every day, of which Party A plants trees in plot B, and Party B plants trees in plot A first and then moves to plot B..
2. There are three grasslands with an area of 5 15 and 24 mu respectively. The grass on the grassland is as thick and grows as fast. The first grassland can feed 10 cows for 30 days, and the second grassland can feed 28 cows for 45 days. How many cows can eat on the third grass for 80 days?
3. A project, contracted by both parties, can be completed in 2.4 days and needs to be paid 1800 yuan; Contracted by Team B and Team C, it can be completed in 3+3/4 days, and it needs to be paid 1500 yuan; Contracted by two teams, Party A, Party B and Party C, it can be completed in 2+6/7 days at a cost of 1.600 yuan. On the premise of ensuring the completion within one week, which team will spend the least?
There is a rectangular iron block in the cylindrical container. Now turn on the tap and pour the water into the container. In 3 minutes, the water surface is just above the top of the cuboid. /kloc-After 0/8 minutes, the container has been filled with water. It is known that the height of a container is 50 cm and the height of a cuboid is 20 cm. Find the ratio of the bottom area of a cuboid to the bottom area of a container.
Two bosses, A and B, bought a fashion at the same price, and B bought 1/5 sets more than A, and then they sold them at profit margins of 80% and 50% respectively. After both of them were sold out, A still made more profits than B, just enough for him to buy 65,438+00 sets of this fashion, which A bought at the beginning.
6. There are two water pipes A and B, and water is injected into two pools with the same size at the same time. At the same time, the water injection ratio of A and B is 7: 5. After 2+ 1/3 hours, the sum of the water injected into A and B is just a pool. At this time, the water injection rate of pipe A is increased by 25%, while pipe B remains unchanged.
Xiao Ming walks from home to school in the morning. When he ran halfway, his father found that Xiao Ming's math book was left at home, and then he rode to deliver it to Xiao Ming. When he caught up, Xiao Ming still had 3/ 10 to go. Xiao Ming got on his father's car at once and was sent to school by his father, so Xiao Ming arrived at school five minutes earlier than walking alone. How long does it take Xiaoming to walk from home to school?
8. Car A and car B both start from place A and pass through place B to place C. The distance between the two places is equal to the distance from place B to place C. The speed of car B is 80% of that of car A. It is known that car B started earlier than car A 1 1 minute, but stayed in place B for 7 minutes, but car A drove all the way to place C. Finally, car B was later than car A..
9. Two cleaning vehicles, A and B, perform road cleaning tasks between things. It takes 10 hour for car A to be cleaned alone, and 15 hour for car B to be cleaned alone. Two cars leave from east and west at the same time. When they met, car A was cleaner than car B12km. How many kilometers is it between East and West?
/kloc-4 containers of 0/0.3 tons, 5 containers of 2.5 tons, 1 0.5 tons/4 containers, and 7 containers of1ton. So how many cars with a load of 4.5 tons are needed to transport all the containers at once?
Comprehensive Training of Mathematical Application Problems in Primary Schools (02)
1 1. Both the master and the apprentice * * * processed 170 parts, and the number of parts processed by the master was 1/3 more than that processed by the apprentice, so how many parts did the apprentice process?
12. Both a cart and a car drive from A to B, and the speed of the cart is 80% of that of the car. It is known that the big car started 17 minutes earlier than the small car, but it stopped at the midpoint of the two places for 5 minutes before continuing to B. However, after the small car started, it went straight to the second place without stopping. Finally, the bus came second before the bus. It is also known that the bus departs from the first place at 10 in the morning. So when did the bus catch up with the bus in the morning?
13. For a manuscript, it takes 14 hours for Party A to type alone, and 20 hours for Party B to type alone. If Party A types 1 hour first, then Party B types 1 hour instead of Party A, and then Party A types 1 hour instead of Party B. .................................................................
1There are 3 yellow balloons in 4.2 yuan and 2 flower balloons in 3 yuan. The school * * * bought 32 balloons, 4 of which were fewer than yellow balloons. What balloons do schools spend more money on?
15. The sailing speed is 60m/min. In a river with a current speed of 20 meters per minute, the ship travels from the upstream port to the downstream place, and then returns to its original place. * * * How many meters did the ship walk from the upstream port to the downstream in 3 hours and 30 minutes?
16. Granary A contains 43 tons of flour and Granary B contains 37 tons of flour. If the flour from granary B is loaded into granary A, the remaining flour after granary B is full accounts for 1/2 of granary B's capacity. If the flour from granary A is put into granary B, after granary B is full, the remaining flour from granary A accounts for 1/3 of granary A's capacity. How many tons of flour can each granary hold?
17. When A is divided by B and B is divided by C, the quotient is equal and the remainder is 2. The sum of A and B is 478. So what is the sum of a, b and c?
18. A car traveling from A to B will arrive 1 hour later than the original time if it slows down 10%. If you drive at the original speed 1 80km, you will arrive1hour earlier than the original time. What's the distance between a and b?
19. A school participated in the military training queue performance competition and organized a phalanx team. If there are 60 students in each class, there must be at least 4 classes in this phalanx. If there are 70 students in each class, there must be at least 3 classes in this phalanx. How many people should this phalanx consist of?
20.a, B and C lathes process square and round parts. It is known that two out of every three parts machined by lathe are round; Three out of every four parts machined by lathe B are round; Four fifths of the parts processed by lathe C are round. On this day, three lathes * * * processed 58 round parts, and the number ratio of square parts processed was 4: 3: 3. So how many parts were processed by the three lathes on this day?
Comprehensive Training of Mathematical Application Problems in Primary Schools (03)
2 1. The length of circular metal wire is 30m, and three metal wires with length a are intercepted and five metal wires with length b are intercepted. If two metal wires with length b are intercepted, the remaining metal wires are 0.4m shorter, and if two metal wires with length a are intercepted, they are 2m shorter. How many meters is the length a?
22. A company wants to transport two kinds of building materials, A and B, to the construction site. Building materials A weigh 700kg each, including 120 * * *, and building materials B weigh 900kg each, including 80 * * *. It is known that a car can transport up to 4 tons at a time, so how many times do five identical cars have to be transported at the same time?
23. The distance from Wang Lijia to the school is longer than the distance to the gymnasium 1/4. One day, Wang Li watched the game in the gym and walked home in 17 minutes. After a short rest, it took him 25 minutes to walk to school, which was slower than coming back from the gym 15 meters. How far is it from Wang Lijia to school?
24. Master and apprentice cooperate to complete a project. Because of their good cooperation, the master's work efficiency has been improved110, and the apprentice's work efficiency has been improved 1/5. After six days of cooperation, two-fifths of the whole project was completed, and then the apprentice worked alone for six days. At this time, the project still has 65438+.
25. Students in five classes of Grade Six planted 65,438+000 trees. As we all know, the number of trees planted in each class is different, and the ranking from the most to the least is just 1, 2, 3, 4 and 5 classes. It is also known that the number of trees planted in 1 is the sum of the number of trees planted in Class 2 and Class 3, and the number of trees planted in Class 2 is the sum of the number of trees planted in Class 4 and Class 5.
26. A runs 13 km per hour, B runs 1 1 km per hour, and B runs 20 minutes longer than A. As a result, B runs 2 km longer than A. How many kilometers did B run?
27. There are two cylindrical containers, A and B, with inner diameters of 6 cm and 8 cm respectively. Container A is full of water and container B is empty. All the water in container A was poured into container B, and the water depth in container B was measured to be 2 cm lower than 7/8 of the container height. What is the height of the container?
28. The cargo 104 tons is transported by 9-ton truck. It is known that a car needs 1 hour for each round trip. In fact, every time the car is loaded 1 ton, it can be completed a few hours in advance.
29. On the first day, master and apprentice processed 225 parts, and on the second day, new technology was adopted. The number of parts processed by the master increased by 24% compared with the first day, and the number of apprentices increased by 45%. Two people processed 300 parts. How many parts did the master process the next day? How many parts did the apprentice process?
30. Struggle Primary School organizes sixth-grade students to go camping and training in Baihua Mountain, and the journey is increased by 2 kilometers every day. I went for four days and came back for three days. How many kilometers is the school from Baihua Mountain?
Comprehensive Training of Mathematical Application Problems in Primary Schools (04)
3 1. The standard for charging electricity in a certain place is: the monthly electricity consumption does not exceed 50 degrees, and the electricity fee is charged at 50 cents per degree; If it exceeds 50 degrees, the excess will be charged at 80 points per degree. Every month, user A pays 3 yuan and 30 cents more than user B. How many kWh did users A and B use this month?
Master Wang plans to process a batch of parts in two hours. When there were 160 parts left, the machine broke down and the efficiency was lower than before 1/5. As a result, the task was completed 20 minutes later than originally planned. How many parts are there in this batch?
33. Mom gave Honghong some money to buy New Year cards, including three kinds of cards: A, B and C. Each card of A is 1.20 yuan. How much did Mom give Hong Hong to buy one card instead of eight cards B and six cards B? How much is the second card?
34. An old man has five sons and three houses. Before he died, he made a will and gave three houses to his three sons. As compensation, the three sons who were assigned to the house each took out 1.200 yuan and divided it equally among the two sons who were not assigned to the house. Everyone says this distribution is fair and reasonable, so how much is each house worth?
35. Xiaoming and Xiaoyan have less than 20 picture books. If Xiaoming gives Xiaoyan an A, Xiaoming's picture book is twice as big as Xiaoyan's. If Xiaoyan gives it to Xiao Amin, Xiao Ming's picture book is three times as big as Xiaoyan's. How many picture books do Xiaoming and Xiaoyan have?
36. There are three kinds of balls *** 160. If 1/3 of the red ball, 1/4 of the yellow ball and 1/5 of the white ball are removed, 120 remains. If 1/5 of the red ball, 1/4 of the yellow ball and 1/3 of the white ball are removed, 1 16 remains. How many yellow balls are there? (2) How many red balls and white balls are there?
37. My father, brother and sister are all 64 years old now. When my father was three times as old as my brother, my sister was nine years old. When my brother is twice as old as my sister, my father is 34 years old. How old are they now?
38.B is between A and C, and A delivers letters from B to A.. 10 minutes later, B delivers another letter from B. 10 minutes later, C found that A and B had just reversed the two letters, so he rode from B to catch up with A and B in order to transfer the letters. It is known that a and b have the same speed.
39. There are 94 workers in Workshop A and Workshop B, processing 1998 bamboo chairs every day. Due to different equipment and technology, each worker in Workshop A can only produce 15 bamboo chairs per day, while each worker in Workshop B can produce 43 bamboo chairs per day. How many more bamboo chairs does Workshop A produce every day than Workshop B?
40. It takes 10 minutes for Party A to go home from school, and 14 minutes for Party B. It is known that the distance for Party B to go home is 1/6 longer than that for Party A, and Party A walks 12 meters longer than that for Party B every minute. So how many meters is the distance for Party B to go home?
Comprehensive Training of Mathematical Application Problems in Primary Schools (05)
4 1. The cost of a commodity per piece in 72 yuan was originally sold at a fixed price, and 100 pieces can be sold every day, and the profit of each piece accounts for 25% of the cost. Later, it was sold at 90% of the fixed price, and the daily sales volume increased to 2.5 times. According to this calculation, how many yuan does the daily profit increase?
42. The speed ratio of the two trains A and B is 5: 4. The second train leaves from Mile Mile for Station A.. When it is 72 kilometers away from Miley Miley, the first train goes from Station A to Miley Miley Miley. The ratio of the distance between the two trains is 3: 4, so what is the distance between Station A and bilibili?
43. There are 35 monkeys, big and small, who go to pick peaches together. In the absence of the Monkey King, a big monkey can pick 15kg and a small monkey can pick 1 1kg in an hour. When the Monkey King is present to supervise, each monkey, regardless of size, can pick 12kg per hour.
44. There are first prize and second prize in the math contest. It is known (1) that the ratio of winners in two schools is 6: 5. (2) The sum of the winners of the two schools in the coming year will account for 60% of the total winners of the two schools. (3) The ratio of winners of the two schools is 5: 6. Ask a school to win the second prize.
45. It is known that the walking speed ratio of Xiaoming and Xiao Qiang is 2: 3, and that of Xiao Qiang and Xiaogang is 4: 5. It is known that Xiao Gang walks 420 meters more than Xiao Ming in 10 minute, so how many meters does Xiao Ming walk less than Xiao Qiang in 20 minutes?
46. It was originally planned to process 15 pieces a day, which could be completed in a few days. When 3/5 of the processing tasks are completed, the efficiency is improved by 20%. Therefore, the task was completed 65,438+00 days ahead of schedule. How many parts are there in this batch?
47.a and B competed in the10000m race on the 400m circular track. They started from the same starting point at the same time. At first, the speed of A was 8m/s, and the speed of B was 6m/s. Every time I caught up with B, the speed of A dropped by 2m per second, and the speed of B dropped by 0.5m per second. This continued until A found B catching up from behind for the first time.
Xiao Ming goes to school from home. If he walks 1.5km more every hour than before, he only needs 4/5 of the original time. If he walks 1.5km less per hour than before, how long will it take him to walk this section?
49. A, B, C and D are all 64 years old now. When a is 2 1 year, b is1year; When A/Kloc-0 was 8 years old, C was three times that of D. How old is D now?
50. A batch of parts was originally planned to process 30 pieces a day. When processing 1/3, due to the improvement of technology, the work efficiency increased by 10%, and the task was completed four days ahead of schedule. How many parts are there in this batch?
Comprehensive Training of Mathematics Application Problems in Primary Schools (06)
5 1. The escalator runs upward at a constant speed. A boy and a girl walked up the escalator at the same time. Boys are twice as fast as girls. It is known that the boy took 27 steps to reach the top of the escalator, while the girl took 18 steps to reach the top. How many steps are there in the exposed part of the escalator?
52. Two piles of apples are the same weight. The first pile sells for 2/3, and the second pile sells for 50 kilograms. If there are fewer apples left in the first pile than in the second pile, how many kilograms are left in the two piles?
53. Two cars, A and B, start from place A at the same time and travel between place A and place B. It is known that the speed of car A is faster than that of car B. After the first and second encounters of the two cars, they mix with place C. What is the speed of car A?
54. The ship went back and forth from A to B for two hours, and it came back smoothly, 8 kilometers faster than when it went, so the second hour was 6 kilometers longer than the first one. Find the distance between a and B.
55. Two cars, A and B, start from A and B respectively, and keep going back and forth between A and B. It is known that the speed of A car is 15km/h, and the difference between the third venue and the fourth venue of A and B is 100km. Find the distance between a and B.
56. Someone walked along the moving escalator from top to bottom for 7 minutes and 30 seconds, while he only walked along the escalator from bottom to top for 1 minute and 30 seconds. If this person doesn't walk, how long does it take to take the escalator from bottom to top? If there is a power failure, how long will it take this person to walk from the bottom to the top along the escalator?
57. The bottom area ratio of two cylindrical containers A and B is 5: 3. The water depth of container A is 20 cm, and that of container B is 10 cm. Then, the same amount of water is injected into the two containers to make the water depth in the two containers equal. How many centimeters is the water depth at this time?
58. The distance between A and B is 207 kilometers. Two cars, A and B, leave from A to B at 8: 00 at the same time, with speeds of 60 km/h and 54 km/h respectively. Car C leaves from B for A at 8: 30 at a speed of 48km/h. What time is it when the distance between car C and car A and car B is equal?
59. The circumference of a rectangle is 130 cm. If its width increases by 1/5 and its length decreases by 1/8, a new rectangle with the same circumference will be obtained. Find the area of the original rectangle.
60. There is a rectangle with an aspect ratio of 5: 2 and a diagonal of 29 cm. Find the area of this rectangle.
Comprehensive Training of Mathematical Application Problems in Primary Schools (07)
6 1. There is an orchard. Last year, there were 60 more fruit trees than those that did not bear fruit. There are 160 fruit trees bearing fruit this year. At this time, the number of fruit trees that bear fruit is exactly five times that of those that do not bear fruit. How many fruit trees are there in the orchard?
62. Xiaoming walks from A to B, while Li Gang walks from B to A on a motorcycle. 48 minutes later, they met. Li Gang returned to B immediately after arriving at A, and caught up with Xiao Ming 16 minutes after the first meeting. If Li Gang kept going back and forth between A and B, how many times did Li Gang catch up with Xiao Ming when he got to B?
63. Go 100 meters, Xiaoming will go 180 steps, and Dad will go 120 steps. Father and son set out from the same place and the same direction at the same time. If it takes the same time to walk every step, how many steps does his father have to take to come back after walking 450 meters?
64. A ship sails between two ports at a speed of 6 kilometers per hour. It takes 4 hours to sail downstream and 7 hours to sail upstream. Find the distance between two ports.
65. There are three cars, A, B and C. Each car runs from A to B at a certain speed. B leaves later than C 10 minutes, and catches up with C 40 minutes after departure; A leaves later than B 10 minutes, and catches up with C after 60 minutes. How many minutes did A catch up with B?
66. Party A and Party B cooperate to complete a job. Thanks to their good cooperation, Party A's work efficiency is improved by110, and Party B's work efficiency is improved by 1/5. Party A and Party B cooperated for 6 hours to finish the work. If Party A does it alone, it needs 1 1 hour.
67. Five students, A, B, C, D and E, stood in a horizontal row with 20 flags in their hands. Now we know that the students standing on the right of C * * are holding 1 1 flags, and the students standing on the left of B * * are holding1flags. How many flags are there in each?
68. Xiaoming ran a circle on the 360-meter-long circular runway. He is known to run 5 meters per second in the first half and 4 meters per second in the second half. How long did it take him in the second half?
In order to measure the length and speed of the passing train, Xiaoying and Xiaoming took two stopwatches. Xiaoying used one watch to record the train passing in front of him for 15 seconds, and Xiaoming used another watch to record the train passing from the first telephone pole in front and the second telephone pole in the back for 18 seconds. Knowing that the distance between two telephone poles is 60 meters, we can find out the total length and speed of the train.
70. Xiaoming walks from home to school in the first half and rides a bike in the second half. Go home from school, take the bus for the first time 1/3, and walk for the second time 2/3. As a result, I spent 20 minutes more time at school than at home. How many kilometers is Xiaoming's distance from home to school?
1. The length of circular metal wire is 30m, and three metal wires with length A and five metal wires with length B are intercepted. If two metal wires with length b are intercepted, the remaining metal wires are 0.4m shorter, and if two metal wires with length a are intercepted, they are 2m shorter. How many meters is the length a equal to?
2. A company wants to transport two kinds of building materials, A and B, to the construction site. Building materials A weigh 700kg each, including 120 * *, and building materials B weigh 900kg each, including 80 * * *. It is known that a car can transport up to 4 tons at a time, so how many times do five identical cars have to be transported at the same time?
3. The distance from Wang Lijia to the school is longer than the distance to the gymnasium 1/4. One day, Wang Li watched the game in the gym and walked home in 17 minutes. After a short rest, it took him 25 minutes to walk to school, which was slower than coming back from the gym 15 meters. How far is it from Wang Lijia to school?
4. Master and apprentice cooperate to complete a project. Because of their good cooperation, the master's work efficiency has been improved110, and the apprentice's work efficiency has been improved 1/5. After six days of cooperation, two-fifths of the whole project was completed, and then the apprentice worked alone for six days. At this time, the project still has 10.
5. Students in five classes of Grade 6 planted 65,438+000 trees. It is known that the number of trees planted in each class is different, and the ranking from the most to the least is 1 class, class 2, class 3, class 4 and class 5. It is also known that the number of trees planted in 1 is the sum of the number of trees planted in Class 2 and Class 3, and the number of trees planted in Class 2 is the sum of the number of trees planted in Class 4 and Class 5.
6. A runs 13 km per hour, B runs 1 1 km per hour, and B runs 20 minutes longer than A. As a result, B runs 2 km longer than A. How many kilometers did B run?
7. There are two cylindrical containers A and B with the same height, and their inner diameters are 6 cm and 8 cm respectively. Container A is full of water and container B is empty. All the water in container A was poured into container B, and the water depth in container B was measured to be 2 cm lower than 7/8 of the container height. What is the height of the container?
8. Goods 104 tons, transported by truck with a load of 9 tons. It is known that a car needs 1 hour for each round trip. In fact, the car loads 1 ton every time, so it can be completed several hours in advance.
9. On the first day, the master and apprentice processed 225 parts, and on the second day, new technology was adopted. The number of parts processed by the master increased by 24% compared with the first day, and the number of apprentices increased by 45%. The two men processed 300 parts. How many parts did the master process the next day? How many parts did the apprentice process?
10. Struggle Primary School organized sixth-grade students to go camping and training in Baihua Mountain, and the trip increased by 2 kilometers every day. I went for four days and came back for three days. How many kilometers is the school from Baihua Mountain?
1 1. The standard for charging electricity in a certain place is: the monthly electricity consumption does not exceed 50 degrees, and 50 points are charged for each degree; If it exceeds 50 degrees, the excess will be charged at 80 points per degree. Every month, user A pays 3 yuan and 30 cents more than user B. How many kWh did users A and B use this month?
12. Master Wang plans to process a batch of parts in 2 hours. With 160 parts left, the machine broke down and the efficiency decreased 1/5. As a result, the task was completed 20 minutes later than originally planned. How many parts are there in this batch?
13. Mom gave Honghong some money to buy New Year cards, including three kinds of New Year cards: A, B and C. Each card of A is 1.20 yuan. How much did Mom give Hong Hong to buy one card instead of eight cards B and six cards C? How much is the second card?
14. An old man has five sons and three houses. Before his death, he made a will and divided three houses among his three sons. As compensation, each of the three sons who were assigned to the house took out 1200 yuan and divided it equally among the two sons who were not assigned to the house. Everyone says this distribution is fair and reasonable, so how much is each house worth?
If it's not enough, come here and find it: /q? C4 % C4 % EA % BC % B6 % B0 % C2 % CA % FD & amp； Lm = 0& Search and search. CT = 17 & amp； pn = 0 & ampikaslist & amprn= 10