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Application problems and answers of mathematical equations in grade one of junior high school
The goods of Party A, Party B and Party C are 167 tons. The goods of Party A are 5 tons less than those of Party B, and the goods of Party C are 3 tons more than those of Party A. How many tons are the goods of Party A, Party B and Party C respectively?

2. The vegetable field is 975 hectares, and vegetables, tomatoes and celery are planted. The area ratio of vegetables to tomatoes is 3︰2, and the area ratio of tomatoes to celery is 5︰7. What are the areas of these three vegetables?

3. Villages A, B and C raised 6.5438+0.4 million yuan to run schools. Through negotiation, the proportion of capital contribution of villages A, B and C is 5: 2: 3. Ask them how much each of them should invest.

4. During the construction, the constructors used the concrete of No.1 Middle School, which was made of water, cement, yellow sand and gravel. The weight ratio of these four raw materials is 0.7: 1: 2: 4.7. How many kilograms of water, cement, yellow sand and gravel do you need to mix this concrete?

Xiaoming went out to travel for four days. It is known that the sum of four days is 65. What is four days?

6. Xiaohua randomly finds a number on the calendar, and finds that the sum of it and the five numbers of up, down, left and right is 85, and asks Xiaohua to find the number.

There are three days in the same column on the calendar, and the sum of the dates is 75. What was the first date?

Solve the problem with formula (2)

-distribution problem.

Team A and Team B have 15 cars. Now 10 cars are transferred to two teams, which makes the number of cars of Team A half that of Team B. How many cars should be allocated to the two teams?

There are fewer girls than boys in a class. If the number of girls increases by 3 and the number of boys decreases by 3, then the number of girls equals the number of boys. How many boys and girls are there?

3.x09 There are 85 workers in a workshop, each of whom can process 16 large gears or 10 small gears on average every day. Knowing that two big gears and three small gears are complete sets, how should we arrange the labor force to make the products just complete sets?

4.x09 If a classmate does five math problems every hour, he can finish them at the scheduled time. When he finished the 10 problem, the efficiency of solving the problem increased by 60%, so he not only finished it three hours in advance, but also did six more problems. How many questions does he plan to do? How many hours will it take to finish?

5.x09 Xiaoli spent 18 yuan in the fruit shop and bought 6 Jin of apples and oranges. It is known that each kilogram of apples is 3.2 yuan, and each kilogram of oranges is 2.6 yuan. How many kilograms of apples and oranges did Xiaoli buy?

6.x09 warehouse a has 200 tons of coal, and warehouse b has 80 tons of coal. If warehouse A transports 15 tons per day and warehouse B transports 25 tons per day, how many days does it take for the two warehouses to store coal on average?

7.x09 There are 50 tons of water in two pools, 5 tons of drainage in pool A and 8 tons of water in pool B.. At this time, the water in pool A is 3 tons less than that in pool B, so how many tons were there in pool A and pool B?

8.x09 There are 55 people in a team, and each person digs 2.5 cubic meters of soil or transports 3 cubic meters of soil on average every day. In order to arrange the labor force reasonably and transport the excavated soil in time, how should the number of people digging and transporting soil be distributed?

Solve the problem with formula (3)

-profit and loss problem workload and discount.

1.x09 Fertilize a wheat field with a few kilograms of chemical fertilizer, 6 kilograms per mu, lacking 17 kilograms; The yield per mu is 5 kg, and the yield is 3 kg more. How many acres is this wheat field?

2.X09 graduates are seated in the auditorium. 1 There are three people on the bench, but there are no more than 25 people. 1 There are four people sitting on the bench, and just four benches are empty. How many graduates are there? How many benches are there?

3.x09 Put a batch of goods into a batch of boxes. If each box contains 10, there are 6 pieces left; If each box contains 13, then a box only contains 1. How many goods and boxes are there respectively?

4.x09 There was a ***20-question math contest, which stipulated that 5 points were deducted for doing one question correctly, 2 points were deducted for each wrong question or not, and Xiao Jing got 86 points. How many questions did Xiao Jing answer correctly?

5. To build a road, it takes 20 days for Team A to complete it alone and 12 days for Team B. Now, after Team A completes it alone for 4 days, how many days will it take for Team A and Team B to complete it together?

6. Some people read a book, the first day they read 20 pages, the second day they read the whole book 14, the third day they read the whole book 13, and the fourth day they read the whole book 25. How many pages are there in this book?

7. For a certain coat, the initial installation cost will be increased by 50%, and then it will be sold at a 20% discount, which will generate profits in 80 yuan. How much is this coat?

8. Some clothes are on sale in different seasons. If each piece of clothing is 50% off on the basis of the marked price, it will lose 60 yuan; And if it is sold at 20% off the list price, it will earn 120 yuan. What is the list price and cost of this dress?

9. With the change of seasons, a commodity will be sold at a discount. If you sell at a 15% discount on the pricing, you will lose 25 yuan; if you sell at a 10% discount on the pricing, you will earn 20 yuan. What is the price of this commodity?

Solve the problem with formula (4)

-Travel issues.

1. The distance between the two stations is 168km. The local train departs from Station A at a speed of 36 kilometers per hour, and the express train departs from bilibili at a speed of 48 kilometers per hour.

(1) Two trains leave at the same time, in opposite directions. How many hours did they meet?

(2) The local train starts first 1 hour, and drives in the opposite direction. How many hours does it take for the express train to meet the local train?

Party A and Party B leave from the same place and go to a certain place. Party A walked 4 kilometers every hour. After Party A walked 16 km, Party B caught up with Party A at a speed of 12 km/h by bike. How many hours can Party B catch up with Party A after departure?

3.a and B practice the 50-meter short distance race. A runs 7 meters per second and B runs 6.5 meters per second.

(1) After a few seconds, A leads B 2 meters?

(2) If A lets B run 4 meters first, how many seconds can it catch up with B?

5.x09 Xiaoming is away from Xiaomei's home1.8km.. One day, Xiaoming and Xiaomei set out from their respective homes at the same time and walked to each other's home. The famous dog and Xiaoming set off together. The puppy first ran to pick up Xiaomei, then ran back to Xiaoming, and then ran to Xiaomei ... and kept running between Xiaoming and Xiaomei. It is known that Xiaoming is 50m/min and Xiaomei is 40m/min.

6.x09 A and B practice running on the 400-meter circular track. A runs 5.5 meters per second and B runs 4.5 meters per second.

(1)x09 B runs first 10 meter, and then A and B start in the same place and direction. How long will it take them to meet for the first time?

(2)x09 B runs 10 meter first, and then A and B start from the same place back to back. How long will it take them to meet for the first time?

(3)x09 A and B set out at the same place and direction at the same time. How long did it take them to meet for the first time?

(4)x09 A runs 10 meter first, and then B starts from A, with the same location and direction. How long will it take them to meet for the first time?

7. A ship is sailing between two docks. The current speed is 3 kilometers per hour. It takes 2 hours to sail downstream and 3 hours to sail upstream. How to find the distance between two docks?

8.a and B run on a 400-meter-long circular track. If they run in the same direction, they will meet every minute. If they run in the opposite direction, they meet every 40 seconds. It is known that A runs faster than B. What are the speeds of A and B?

9. Two people, A and B, rode bicycles in opposite directions from two places 65 kilometers apart. The speed of A is 17.5km, and the speed of B is 15km. A few hours later, the distance between them was 32.5 kilometers.

10, the car is driving on the expressway at a speed of 72 kilometers per hour. When driving to the silent valley, the driver honked his horn and heard an echo four seconds later. How far is the valley in the car? (The speed of sound is 340 meters per second)

Solve the problem with formula (5)

-Other questions.

1, x09 brain input an article of 1, 800 words, it takes 30 minutes for Xiao Ming and 45 minutes for Xiao Hong. Now it is 1 1: 10. If Xiaoming and Xiaohong cooperate, they can do it at 1 1: 30. Please explain your reasons.

2. The school organizes teachers and students to watch movies. There are 950 students and 27 teachers. The theater ticket office said:

Please design a ticket purchase plan that you think is the most economical and work out how much it costs to buy a ticket.

A shop deals in a commodity. Because the purchase price is reduced by 5% and the selling price remains unchanged, the profit rate is increased from m% to (m+6)%. What is the value of m?

4. A math contest was held in the first day of a school, and 80 people signed up for it. The overall average score of the contest is 63, the average score of passing schools is 72, and the average score of failing students is 48. What is the passing rate of this contest?

5. There is a three-digit number, and its unit number is 1 more than hundred digits, and the ten-digit number is 1 less than half of the one-digit tree word. If the single digit is regarded as hundreds, the hundred digits as tens and the tens as single digits, then the sum of the new number and the original number is 16 165438.

6. One of the six figures is 2. If the number 2 in his single digits is moved to the first place, the order of other digits remains the same, and the new number is the original number. Can you find the original six figures?

7. Dahong and Xiaohong received lucky money of *** 1000 yuan in the New Year. Dahong deposits his lucky money in the bank according to one-year education savings, with an annual interest rate of 1.98%, which is exempt from interest tax; Xiaohong bought his lucky money as a bond with a monthly interest rate of 2. 1.5 ‰, but he had to pay 20% interest tax. After a year, the income of the two people is exactly the same. How much is their lucky money?

8. Pour water from a rectangular container with a bottom of 20cm×20cm into a rectangular iron box with a length, width and height of 16cm, 10cm and 5cm respectively. When the iron box is filled with water, how much does the water drop in the cuboid container?

9. The purchase price of a commodity in 800 yuan is 1200 when it is sold. Later, due to the backlog of this commodity, the store was prepared to sell it at a discount, but how much discount should it be to maintain a profit margin of 5%?

10, there is a narrow crossing that allows one-way traffic. Usually, you can pass 9 people every minute. One day, Mr. Wang came to the crossroads. At this time, there are 36 people waiting to pass in front of him (assuming that Mr. Wang's crossing time is ignored). It takes seven minutes to get to school after crossing the intersection.

(1)x09 If you make a detour at this time, it will take 15 minutes to get to school. In order to save time, should Mr. Wang choose a detour or a crowded intersection to go to school?

(2)x09 If, with the maintenance of Mr. Wang and others, the order returns to normal in a few minutes (during the maintenance of order, if three people pass through the crossing every minute), as a result, Mr. Wang asked how long it would take to maintain order through the crossing six minutes earlier than in the crowded situation.

1 1 Try to find out the problem and discuss it according to the following situations.

A class organized a spring outing to the scenic spot. Most students go by bus, with an average speed of 24 kilometers per hour. Four students in charge of logistics left the school bus in half an hour, with a speed of 60 kilometers per hour. Two groups of people reached the foot of the mountain at the same time. When they arrived, they found it expensive to go up the mountain by cable car, and they couldn't browse the scenery along the way. So everyone agreed that the big troops would go up the mountain on foot, and the fourth logistics team would be changed to an advance team, taking a cable car up the mountain and holding activities at the top of the mountain.

1. Set x tons of Class A goods.

Then the second commodity (x+5)/2

Class C goods 0.5x+3

x+(x+5)/2+0.5x+3= 167

2x= 16 1.5

X=80.75 A.

(x+5)/2=42.875 B。

0.5x+3=43.375 degrees Celsius.

2. If the area of tomatoes is X, the area of vegetables is 3/2x, and the area of celery is 7/5x, then

3/2x+x+7/5x=975

x=250

Green vegetables 250*3/2=375

Celery 250*7/5=350

3. The investment in Village A, Village B and Village C is 5 million yuan, 2 million yuan and 3 million yuan respectively.

5x+2x+3x= 140

10x= 140

x= 14

Investment in village a14× 5 = 700,000 yuan.

Investment in village b14× 2 = 280,000 yuan.

Investment of Bingcun14× 3 = 420,000 yuan.

4. If the weight of cement is X, water is 0.7x, sand is 2x and gravel is 4.7x, then,

0.7x+x+2x+4.7x=2 100

8.4x=2 100

x=250

250*0.7= 175 water

250*2=500 yellow sand

250*4.7= 1 175 gravel

5. Let the number of the second day of these four days be X, then the numbers of other days are: x- 1, x+ 1, x+2, which means X-1+X+2 = 60 according to the meaning of the question.

6. Let the middle number be x, then the numbers of up, down, left and right are (x-7), (x+7), (x- 1) and (x+ 1) respectively.

In terms of meaning, (x-7)+(x+7)+(x-1)+(x+1)+x = 85.

So 5X=85,

So X= 17,

That is, the number Xiaohua is looking for is 17.

7. It can't be 75. Generally, the vertical column difference of a calendar is 7 days, and the first day is 18, but in this case, the last day is 32, but it's a pity that the maximum is 3 1 day in a month. So as you said, the sum of dates is 72 at the highest and 24 at the lowest, so it is impossible to exceed this range.

Unless it's not a seven-day schedule.

8. Suppose X cars are assigned to Team A, and Team B 10-X cars15+x = (1/2) (28+10-x)+215+x =/.

9. Let the number of boys be x; The number of girls is y.

Y=2/3X-2 X=3/2+3。

Y+3=7/9(X-3)

Brought in: X=30 Y= 18.

10. If X individuals are to be arranged to produce large gears, 85-X individuals are to be arranged to produce small gears.

16X:[ 10 *(85-X)]= 2:3

16X:(850- 10X)=2:3

3* 16X=2(850- 10X)

48X= 1700-20X

68X= 1700

X=25

85-X

=85-25

=60

1 1. It is supposed to be completed within x hours. 5x =10+5 * (1+60%) * (x-2-3)-6, and the solution is X= 12. A: The original plan was to do 5 * 65438.

12. Suppose I bought X kilograms of apples and Y kilograms of oranges.

x+y=6

3.2x+2.6y= 18

The solution is x = 4 and y = 2.

13. suppose that the coal stored in the two warehouses is equal after x days. Equation 200-15x = 80+25x40x =120x = 3 can be listed.

14. let a have x tons and b have 50-x tons.

According to the meaning: x-5+3=50-x+8.

x-2=58-x

2x=60

x=30

50-30=20

15. Excavation: 55(2.5+3)×3 = 30.

Earthmoving: 55-30=25

16.20 mu, 6x- 17=5x+3 gives x=20 mu.

17. There are x benches.

3x+25=4(x-4)

x=29

3x+25= 1 12 people

19. The X box is provided.

13(x- 1)+ 1 = 10x+6

The solution is x=6.

The goods are 6* 10+6=66.

20. set the wrong question x and answer the 20-X question.

20*5-86=(5+2)X

X=2

20-2= 18 questions