1, and the weight ratio of apples in frames A and B is 4: 5. If you take 6 kg from B and put it in A, the weight ratio of the two frames is 5: 4. How many kilograms are there in two frames?

Suppose two boxes * * * have x kilograms.

(4/9X+6):(5/9X-6)=5:4

2. Magnifying the decimal part of a number by 3 times is 4. 1, and magnifying the decimal part by 9 times is 8.3. What is the number?

(1) Integer part+3 times of decimal part =4. 1

(2) Integer part+9 times of decimal part =8.3

2 minus 1

(integer part+9 times of decimal part)-(integer part+3 times of decimal part) =8.3-4. 1.

6 times of fractional part =8.3-4. 1

Decimal part =0.7

Integer part: 2

The number is: 2.7.

3. There is a copper-zinc alloy, and the weight ratio of copper to zinc is 2: 3. Now add 6 grams of zinc to get 36 grams of new alloy, and find the weight ratio of copper and zinc in the new alloy.

Copper: (36-6)÷(3+2)×3= 18

Zinc: (36-6)÷(3+2)×2= 12.

Zinc in the new alloy: 12+6= 18.

Copper: zinc =18:18 =1:1.

4. There is a round flower bed on the playground, and a pot of flowers is placed every 2dm around the flower bed, totaling 157 pots. What is the radius of this flower bed?

Circumference of circular flower bed:

2× 157=3 14 (decimeter)

Radius of circular flower bed:

3 14÷3. 14÷2=50 (decimeter)

In the middle of the track of the sports ground is a rectangle, with a length of 100 m and a width of 40 m, and both ends are semicircular. In order to level the field, eight cars of yellow sand, each with 7 cubic meters, should be laid on the runway as evenly as possible. How do you think it should be distributed? (π takes 3. 14)

Sports ground area:

Rectangular+circular100× 40+3.14× (40 ÷ 2 )× (40 ÷ 2) = 5256 (square meter)

How much yellow sand did you pull?

7×8=56 (m3)

Uniform yellow sand is laid on the runway.

56÷5256≈0.0 1 (m)

6. The number of the base angles of an isosceles triangle is half of the top angle. What is the vertex angle of this triangle?

Think of the base angle as 1.

The vertex angle is two parts.

1 serving:

180÷( 1+ 1+2)=45

The vertex angle is two parts.

45×2=90

7. The circumference and diameter of a circle add up to 20.7 meters. What is the area of this circle?

Circumference =3. 14× diameter

The sum of the circumference and diameter of a circle is 20.7 meters.

That is:

3. 14× diameter+diameter = 20.7m.

Diameter ×(3. 14+ 1)=20.7

Diameter: 20.7(3. 14+ 1)= 5.

Radius: 5÷2=2.5

Area: 3. 14×2.5×2.5.

8. Xiaoming has a 45-day winter vacation, one-third of which is at his grandmother's house in the countryside, two-ninth of which is traveling, and the rest of the time is to rest and study. Please ask a few questions, and please ask three questions and answer them side by side.

1: How much time is left to rest?

1- 1/3-2/9

2: How much time is left to rest?

45÷( 1- 1/3-2/9)

3. How many days does Xiaoming travel in winter vacation?

45×2/9

9. At the beginning of the winter vacation, red scarf volunteers participated in community labor. 50% students sweep the corridor, and two-fifths students carry garbage. Seven of them did both, accounting for 14% of the total number of volunteers. How many volunteers are there? Except the students who sweep the corridor and transport garbage, others clean the windows. How many people clean the windows?

Seven of these students did both, accounting for 14% of the total number of volunteers.

65438+ 04% of the total number of volunteers is 7.

Total number of volunteers: 714% = 50.

Volunteers asked 50% of the students to clean the corridor.

Students sweeping corridors: 50×50%=25

Volunteers have two-fifths of their classmates carrying garbage.

Garbage truck: 50×2/5=20

Except the students who sweep the corridor and transport garbage, others clean the windows. How many people clean the windows?

50-25-20+7= 12

1. Three fifths of the total length of a road has been repaired, and 120 km has not been repaired. How many kilometers is this road?

120÷( 1-3/5)=300

Xiaohong read a novel. On the first day, she read a fifth of the books, and the next day, she read a quarter of the books, leaving 12 1 page. How many pages does this novel have?

12 1÷( 1- 1/5- 1/4)=220

10. Make a batch of clothes with 1200m cloth, in which the amount of cloth for pants is one fifth of that for a coat. How many meters of cloth does it take to make a coat and a pair of trousers?

Coat: 5 copies

Pants: 1 serving

Coat:1200 ÷ (5+1) × 5 =1000

Pants: 1200(5+ 1)= 200.

1 1. There are 30 tons of grain in the warehouse. One fifth of the total grain was transported for the first time and nine thirds for the second time. How many tons were used twice?

30× 1/5+9/2= 10.5

12, processing a batch of parts, Party A 12 days, Party B 15 days. How many days can two teams start working at the same time to complete three-fifths of this batch of parts?

3/5÷( 1/ 12+ 1/ 15)=4

13. The school bought 30 basketballs (more than football12 10). How many footballs did you buy? First, supplement the conditions to make it a fractional division application problem calculated in two steps.

(30- 10)÷ 1/2=40

14. Xiao Ming, Xiao Hu and Xiao Li * * * have stamps of 38 roses. If Xiaoming puts in five roses, Xiao Hu takes out three roses, and Xiao Li takes out his own half, the number of stamps of the three people is equal.

Total+Xiaoming put in 5 roses-Xiaohu took out 3 roses-Xiaoli took out her own half = 3 times the number of stamps for three people (also 3 times that of Xiaoli's half).

38+5-3- Half of Xiaoli = 3 times of Xiaoli's half.

40- half of Xiaoli = 3 times of Xiaoli's half.

40= 3 times half of Xiaoli+half of Xiaoli.

40= 4 times of Xiaoli's half.

Half of Xiaoli: 10

Xiao Li: 20

15. At present, 70 cubic decimeters of wood are used to produce some tables. Each table consists of a desktop and four legs. As we all know, it takes 6 cubic decimeters of wood to make the table top and 2 cubic decimeters of wood to make the table legs. Q: How much wood does it take to make a desktop?

Solution: Suppose 70 cubic decimeters of wood can produce X tables.

6X+2×4×X=70

X=5

How much wood does it take to produce a desktop?

6×5=30

16. Party A and Party B practice long-distance running on the 400-meter circular runway, and at the same time, starting from the same point, Party A's speed is 6 meters per second and Party B's speed is 4 meters per second. How many seconds did B run when A passed Otsuichi Circle? How many laps did you run in one run?

Catch-up Time = Catch-up Distance/Catch-up Speed

400÷(6-4)=200

When A passed Otsuichi Circle, B ran for 200 seconds and A ran for 200 seconds.

A ran 6×200= 1200.

1200÷400=3

A ran three times.

17. All the students in Grade One went to the auditorium for a meeting. If five people sit on each bench, there will be less 10 benches. If six people sit on each bench, there are two benches left. What are the number of students and benches?

Suppose there are x benches.

5×(X+ 10)=6×(X-2)

X=62

18. A bus is 200 meters long and a truck is 280 meters long. They are driving in opposite directions on parallel tracks. It takes 18 seconds from meeting to leaving the parking space. The speed ratio of the bus and the train is 5: 3. How many meters do two cars travel per second?

The distance traveled by two cars from meeting to leaving the parking space is the sum of their lengths.

(200+280)÷ 18=80/3 is the sum of the speeds of two cars.

The speed ratio of passenger cars to trucks is 5: 3.

Bus: 80/3÷(5+3)×5=50/3

Freight car: 80/3÷(5+3)×3= 10

19. One job shall be completed by Party A alone within 20 hours; B do it alone 12 hours. If Party A works alone for 4 hours first, and the rest of Party A and Party B cooperate, how many hours will it take to complete?

Work efficiency A: 1/20

Ergonomics of B:112

( 1- 1/20×4)÷( 1/20+ 1/ 12)=6

After the Wenchuan earthquake, people all over the country donated money and materials to support the disaster-stricken areas. An enterprise donated 600 tents A and B to the disaster area, with a value of 940,000 yuan. It is known that each tent A is 1.700 yuan and each tent B is 1.300 yuan. How many tents a and b are donated?

Suppose tent A has x roofs and tent B has (600-X) roofs.

1700 X+ 1300×(600-X)= 940000

X=400

B Tent 600-400=200

2 1. There is a bottle of pure honey. Pour out a quarter for the first time, then fill it with water. Pour out a third for the second time and then fill it with water; Pour out three quarters for the third time, and then fill it with water. How much water is there in the bottle now?

Go find honey.

First pass: pour out a quarter, leaving three quarters.

Pour out a third for the second time, that is, 3/4 of 1/3, that is, 3/4× 1/3= 1/4.

There are still 3/4- 1/4=2/4= 1/2.

Pour out three quarters for the third time, that is, three quarters of 1/2, that is, 1/2× 3/4 = 3/8.

And 1/2-3/8= 1/8.

Honey is 1/8.

Water is 1- 1/8=7/8.

22. The grain reserves of both parties are 10 ton. If you give a fifth of A to B, now they have the same storage capacity. How many tons of grain do they have each?

One fifth of A went to B, and now they have the same amount of storage.

a×( 1- 1/5)= B+a× 1/5

And a× (1-1/5)+(b+a×1/5) =10.

That is, a× (1-1/5) =10 ÷ 2.

A: 6.25.

B: 10-6.25=3.75

23. Party A, Party B and Party C jointly repair a fence, with Party A and Party B completing 1/3 in five days, Party B and Party C completing the remaining 1/4 in two days, and then Party A and Party C completing it in five days. Remuneration for services of decoration works 600 yuan. How much is A worth?

1/3 Party A and Party B will finish it in 5 days.

The sum of ergonomics of Party A and Party B is1/3÷ 5 =115.

The remaining 1/4 will be completed within two days after Party B and Party C jointly repair it.

Ergonomics of ethylene propylene and (1-1/3) ×1/4 ÷ 2 =112.

The remaining 1/4 was completed in two days, and then it took Party A, Party B and Party C five days to complete.

The working efficiency of A-C is (1-1/3) × (1-1/4) ÷ 5 =110.

Ergonomics of a, b and c

( 1/ 15+ 1/ 12+ 1/ 10)÷2= 1/8

The working efficiency of A is1/8-112 =1/24.

The total work of A is 1/24×(5+5)=5/ 12.

How much should a share cost?

600×5/ 12=250

26. A rectangular steel plate is 24 decimeters long, 10 decimeter wide and weighs 6 kilograms. Cut a sector with a central angle of 120 degrees and a radius of 9 decimeters from this steel plate. How many kilograms does the cut fan-shaped steel plate weigh?

Weight of steel plate per square decimeter

6(24× 10)= 0.025 (kg)

Cut a fan-shaped area with a central angle of 120 degrees and a radius of 9 decimeters from this steel plate.

3.14× 9× 9 ÷ 360×120 = 84.78 (square decimeter)

What is the weight of the fan-shaped steel plate?

0.025× 84.78 = 2.1195 (kg)

27. The father is 47 years old and the son is 20 years old. How many years ago, my father was four times as old as my son? (Equation)

Suppose that X years ago, the father was four times as old as his son.

47-X=(20-X)×4

X= 1 1

28. It is necessary to take the largest triangle on a semicircular steel plate with a diameter of 2 decimeters. What is its area? What is the area of this triangle?

The height triangle with the diameter of the semicircle as the base and the radius of the triangle is the largest triangle.

Its area is 2×(2÷ 1)÷2= 1.

Area of semicircle: 3.14× (2 ÷1)× (2 ÷1) ÷ 2 =1.57.

What is the area of this triangle?

1÷ 1.57= 100/ 157

29. In a division formula, the sum of dividend, divisor, quotient and remainder is 49, the known quotient is 7, and the remainder is 1. What is the dividend?

49- 1-7= frequency divider+frequency divider

Dividend = quotient × divisor+remainder

49- 1-7= quotient× divisor+remainder+divisor

49- 1-7=7× divisor+1+ divisor

4 1- 1=7× divisor+divisor

40=8× divisor

Frequency divider: 40÷8=5

Dividend = quotient × divisor+remainder

Dividend: 7× 5+ 1 = 36

30. Both A and B are bigger than Fang. A said to B, when I was your age this year, you were only 5 years old. B said to A, when I reach your age this year, you will be 17 years old. How old are these two brothers?

Smile:-

Small:-

Big: ———————————————.

Big:-.

Big and small are just three age differences.

Xiaoxiao:-* * * 5 years old

Small age: (big-small) ÷3+ small

( 17—5)÷3+5=9

Big:-* * *17 years old.

Older: [(big-small) ÷3+ small]+(big-small) ÷3.

[( 17—5)÷3+5]+( 17—5)÷3= 13

8. There are 99 students in Class A and Class B. If one tenth of the students in Class A are transferred to Class B, the ratio of students in Class A to Class B is 5: 6. What is the original number of students in these two classes?

Suppose there are x people in class a.

X×( 1- 1/ 10):(99-X+X× 1/ 10)= 5:6

X=99

No.50 grade a

Class b 49

9. Nanning Huxian Development Zone should reclaim a piece of land, level 0.5 hectares every day, and complete the task in 60 days. Now it is required to finish the task 10 days in advance. How many hectares are leveled more than before every day? (column equation solution)

Suppose that X hectares are leveled more every day than before.

0.5×60=(0.5+X)×(60- 10)

X=0. 1

10. Agricultural Bank of China wants to change 220 5 yuan RMB into 20 cents. How much can it change? (Answer in two ways)

5 yuan =50 jiao.

1: 50÷2×220=5500

2: 5×220× 10÷2=5500

Application problems of mathematical equations in seventh grade

Distance type:

1. In the 400-meter race test, Xiao Gang first ran most of the distance at a speed of 6 meters per second, and finally sprinted to the finish line at a speed of 8 meters per second, with a score of 1 minute and 5 seconds. How long did Xiao Gang spend in the sprint?

2. The taxi pricing standard in a certain place is as follows: the journey does not exceed 3km, the starting price is 8 yuan, and the excess is charged per kilometer 1.20 yuan.. If you pay 17.60 yuan by taxi, how many kilometers did Yi * * walk?

3. It takes 7 hours for the bus to go from A to B. After the expressway is opened, the distance is nearly 30 kilometers, and the average speed of the car is increased by 30 kilometers, which takes only 4 hours to arrive. Find out the distance between a and b on the expressway. ..

4. It takes 5 hours and 30 minutes for the plane to fly between two cities, and 6 hours against the wind; The wind speed is 24 km/h, and find the distance between the two cities.

5. The distance between A and B is 16 10 km. A train leaves from A at a speed of 90 kilometers per hour. An express train departs from B at a speed of 140 km/h. If two cars leave at the same time and drive in opposite directions, how many hours do you expect the two cars to meet?

6. Someone takes a boat downstream from A to B and then upstream to C (C is between AB). It takes four hours. It is known that the speed of the ship in still water is 7.5 km/h and the current speed is 0.5 km/h. If the distance between A and C is 8 km, how to find the distance of AB?

7. A correspondent needs to arrive 24 minutes in advance by bike and on foot15km/h, and deliver the letter to a certain place; If you walk 12 kilometers per hour, you will be late 15 minutes. What was the initial time? How far is he going?

8. The distance between A and B is 37 kilometers. A and B set out at the same time and walked towards each other. Half an hour later, they are still 22 kilometers apart. A's speed is 16 km. What's the speed of B?

9. The distance between Station A and bilibili is 365km, and a local train runs from Station A to bilibili at a speed of 65km per hour. After the local train 1 hour, there is another express train from bilibili to Station A, with a speed of 85km/hour. The express train ran for several hours and met the local train.

10. Party A and Party B race around the lake. Around the lake is 400 meters a week, and Party B walks 80 meters every minute. The speed of A is 1 times that of B. If A is in front of B 100 meters, how many minutes will the two meet?

13. 14. Party A is in the east and Party B is in the west. The distance between them is 140km. Party A travels west at a speed of 3.2km/h and Party B travels east at a speed of 3.8 km/h. How many hours will they meet?

Number type:

1. A three-digit number, where the number in the hundredth digit is greater than the number in the tenth digit 1, and the number in the first digit is three times smaller than the number in the tenth digit by two. If the three digits are reversed, the sum of the obtained three digits and the original three digits is 1 17 1, and the original three digits are found.

2. Two digits, twice as many as ten digits. If ten digits and one digit are reversed, the new two digits are 36 larger than the original two digits. How about the original two digits?

3. For a three-digit number, the sum of the numbers on the three-digit number is 15, the hundredth digit is five more than the tenth digit, and the third digit is three times the tenth digit. How to find these three digits?

For two-digit numbers, one digit is four times that of ten digits. If the number of one digit is reversed with the number of the tenth digit, the two digits obtained are 54 larger than the original number. How about the original two digits?

There is a two-digit number, and the number in the tenth digit is twice that in the first digit. If the positions of these two numbers are reversed, the new number is 27 less than the original number. Find this two-digit number.

Work efficiency:

1. Party A and Party B jointly input an article with 50,000 Chinese characters, with Party A inputting 150 Chinese characters every minute and Party B inputting 100 Chinese characters every minute. Now that two people are working together, how long will it take to complete the entry of this article?

2. 1 hectare The lush forest can absorb about 1 ton of carbon dioxide every day, and each person exhales 38 grams of carbon dioxide per hour on average. How many hectares of forest do you need if you want to absorb the carbon dioxide exhaled by 10 thousand people a day? (24 hours a day; The result is retained to two decimal places. )

3. A job can be completed in 3 hours by yourself and 5 hours by yourself. How many hours does it take for two people to work together?

4. Project A will be completed in 20 hours alone, and Project B will be completed in 0/2 hours alone/kloc-. Now Party A works alone for 4 hours, while Party A and Party B work together for the rest. How many hours will it take to finish the rest?

Profit problem:

1. A store marked a certain garment after increasing its purchase price by 40%, and some of them were sold at a 20% discount (that is, 20% off the marked price). As a result, each piece of clothing still earned 15 yuan. What is the purchase price of each piece of clothing?

2. Subscribe for a company's three-year bonds of RMB 654.38+0,000, and the sum of principal and interest after maturity is RMB 654.38+0.24 million. What is the annual interest rate of this bond?

3. The current price of a drug is 56. 1 yuan, which is lower than the original price 15%. What is the original price?

4. A shop sells it. Two pieces of clothes, each piece 120 yuan, one of which earned 30% and the other lost 30%, so is this store profitable or loss-making, or neither profitable nor loss-making?

5. In order to improve the conditions of running a school, the school borrowed 100 yuan from the bank for the construction of the experimental building. The annual interest rate of the loan is 65,438+02%, and the annual interest rate of the building depreciation is 2%. The school has about 1400 students, and only pays loan interest and construction depreciation. How much is the annual experimental fee for each student?

6. A company sells two kinds of sneakers, A and B. Last year, * * * sold12,200 pairs. This year, the sales volume of type A shoes increased by 6% compared with last year, the sales volume of type B shoes decreased by 5% compared with last year, and the total sales volume of two kinds of shoes increased by 50 pairs. How many pairs of shoes did A and B sell last year?

7. The purchase price of a commodity is 400 yuan, the price is 600 yuan, and the profit rate is 5% when it is sold at a discount. Then, how much discount is this commodity on sale?

8. Xiao Zhao went to the store to buy exercise books. When he came back, he asked his classmates, "The shopkeeper told me to give me a 20% discount if I bought more, so I bought 20 copies, which were cheaper 1.60 yuan. Guess how much each book costs? "

9. The cost of a commodity is 200 yuan. If the price is raised by 30% and then sold at a 10% discount, what is the profit of this product?

12. Xiaoming's mother saved a two-year time deposit the year before last, with an annual interest rate of 2.43%. After the expiration of this year, after deducting 20% interest tax, the interest earned just bought Xiaoming a schoolbag worth 97.20 yuan. Ask Xiao Ming's mother how much money she saved the year before last.

Distribution problem:

1. In extracurricular activities, some students take part in group activities. Initially, there were 8 students in each group. Later, they were regrouped, and each group had 12 people, which was 2 less than before. How many students are there?

2. There are 100 people working in A and 88 people working in B. Now 70 people will be transferred from A and B, and the number of people left in A and B is equal. Then how many people should be transferred to A and B respectively?

A class is divided into two groups, the first group has 26 students and the second group has 22 students. According to the number of school activity equipment, how many people should be transferred from the first group to the second group to adjust the number of people in the first group to half of that in the second group?

5. On Arbor Day, Class A planted two kinds of trees, A and B. It is known that the number of trees in Class A is 56, which is more than half of the total number, and the number of trees in Class B is 14, which is less than one third of the total number. How many trees were planted, A and B respectively?

6. School cleaning, a class was divided into two groups, the first group of 26 people cleaned the classroom, and the second group of 22 people cleaned the contract area. This time, according to the needs of the work, how many people should be transferred from the first group to take the second group, so that the number of people in the second group is twice as large as that in the first group?

General type:

1. A wire, cut by half, 1 meter is short, leaving 5 meters. How long is this wire?

3. After dry sea cucumber was flooded, the total amount increased by 8.5 times. How many kilograms does dry sea cucumber have to take to get 380 kilograms of sea cucumber?

4. A class of students went to the community to participate in tree planting. It was originally planned that half the students would take part in labor and plant 40 trees every day. After completing one third, the whole class joined in, and the task was completed one day ahead of schedule. Assuming that everyone's planting efficiency is the same, how many trees have been planted?

5. After bean sprouts were produced, the weight of soybean increased to 4.5 times. How many kilograms of soybeans does it take to produce 90 kilograms of bean sprouts?

6. a wire, cut off half for the first time, cut off the remaining half for the second time, leaving 5cm. How long is this wire?

8. There are three barrels of oil, one barrel weighs 100 kg, the second barrel is 5 kg lighter than the first barrel, and the third barrel is 80% of the second barrel. How much does the third one weigh How many kilograms is the third barrel of oil heavier than the first?

9. There were 328 seventh-grade teachers and students in a school who went out for a spring outing by bus. There are already two school buses that can seat 64 people. How many 44-seat buses do you need to rent?

1 1. The surface of a football is made up of 20% polygonal black and white leather blocks, with a total of 32 pieces. As we all know, the number of black blocks is more than half of the number of white blocks. 2. How many pieces are there?

12. Black powder is made of three raw materials: sulfur, charcoal and nitrate. Their ratio is 2: 3: 15. How many kilograms does it take to make 150 kg black powder?

14. Grade 7 students in a school participated in a public welfare activity, among which 15% students went to promote environmental protection and the rest 170 students went to plant trees and grass. How many students in Grade 7 participated in this charity activity?

15. During the military training, 50 students were arranged in 9 dormitories, and all the dormitories were occupied except one with 4 beds. How many beds are there in each dormitory?

Discuss the problem:

1. According to the regulations of China Civil Aviation, one ordinary class passenger can carry up to 20 kilograms of luggage free of charge, and the baggage ticket is purchased at 65438+ 0.5% of the excess ticket fee. A passenger carries 35 kilograms of luggage and pays the air ticket and baggage fee 1323 yuan. Ask the passengers about the ticket price.

A bank set up a student loan for college students. The annual interest rate of a six-year loan is 6%, and 50% of the loan interest is subsidized by the state finance. A college student expects to repay 20 thousand yuan in turn after 6 years, so what is the amount he can borrow now?

6. A bookstore sells discount book cards for 300 yuan. With this card, you can buy books at a 30% discount in this bookstore. When is it worthwhile to buy books?

8. The school is going to buy a number of desks and chairs. The original order was 120 sets, and each set was 100 yuan. The store said: you can get a discount if you buy more. As a result, the school bought 144 sets, each set was reduced by 3 yuan, but the store took the same amount; Profits. Ask about the cost of each set of tables and chairs.

Graphics volume:

1. Knead a cuboid plasticine with the length, width and height of 30cm, 15cm and 20cm respectively into a cylinder with the bottom radius of 10cm, and find the height of the cylinder.

2. There are a number of rectangular iron ingots with a cross section of 40 cm long and 20 cm wide. Now, how long iron ingots (7.8g/cm3) should be cut to cast 156kg parts?

4. The bottom radius of cylinder A is 1cm, the height is 6cm, and the bottom radius of cylinder B is 2cm. If the volume of cylinder B is twice that of cylinder A, what is the height of cylinder B?

5. A steel plate with a length of 300 cm, a width of 150 cm and a thickness of 1 cm, after forging, the width remains unchanged and the length increases by 60%. What is the thickness of forged steel plate?

6. Cast 12 shots with a diameter of 10cm with cylindrical lead columns. How long should the lead column be cut? (The volume of the ball is)

7. Fill a cylindrical bucket with an inner diameter of 200mm with a bucket of water, pour it into a cuboid iron box with internal length, width and height of 300mm, 300mm and 80mm respectively, and just fill it up, and you can find out the water height of the cylindrical bucket. (accurate to 1mm, and the approximate value of π is 3. 14).

1(09 Anhui province volume) 4. Volunteer A plans to finish some work in the community in a few working days. From the third working day, volunteer B will join the work, and their ergonomics are the same. Therefore, the task will be completed three days in advance, so the number of days that Volunteer A plans to complete the work is .....................

A.8 B.7 C.6 D.5

2(09 Beijing Volume) 18. Solving equations or equations: Since the implementation of new traffic management measures in Beijing, the passenger volume of urban public transport has increased significantly. According to statistics, during the period from 1 June1February 28, 2009, the average daily passenger volume of ground bus and rail transit increased significantly.

3(09 Fuzhou, Fujian) 17. (8 points for each small question) (2) It takes 60 hours to sort out a batch of books if one person does it alone. At present, some people spend an hour tidying up, plus 15 people to work with them for another two hours, just finishing tidying up. Assuming everyone's work efficiency is the same, how many people will arrange the ranking first? .

4(09 Ningde, Fujian) 16. Teacher Zhang leads X students to visit the zoo. It is known that each adult ticket is 10 yuan, and each student ticket is 5 yuan. The total cost of admission is y yuan, so y =

5(09 Ningde, Fujian) 2 1. (The full mark of this question is 8) A magazine reported: "On June 5438+February 15, 2008, direct sea, air and postal services between the two sides of the strait were launched, and the' three links' were basically realized. The most direct benefit of the "three links" is to save time and cost. According to the calculation, air transport is average. According to the information in the article, how many people travel between the two sides of the strait by air and sea every year? * * can save people 29 million hours.

6(09 Anshun, Guizhou) 24. (Full mark of this question 10) During the May Day, Xiao Ming, Liang Xiao and other students went to the park with their parents. The following is a conversation between Xiao Ming and his father when they buy tickets (pictured). Try to answer the following questions according to the information in the picture:

(1) How many adults and students did Xiaoming go to?

(2) Please help Xiao Ming think about which way to buy tickets is more economical? Explain why.

I'm exhausted after looking for it for a long time! Pick the best for me.

The word limit can only be sent so much. If it is not enough, I will give it to you. ...