Assignment problems of linear equations of one variable in the first grade of junior high school with procedures. 10 questions are required.

Provide questions: Some answers to questions you don’t know:

1. Multiply relationship

(1) It is known that the number A is more than three times the number B 12. The sum of the two numbers A and B is 60. Find the number of B.

(2) It is known that the number A is 5 less than the number B, and the number A is 65 greater than the number B. Find the number B.

(3) The output value of a certain factory this year is three times last year’s output value, which is 250,000 less. The total output value of this year and last year is 750,000. Find the output value of the factory this year.

2. Percentage question:

(4) A depositor deposited 12,000 yuan in the bank for one year and received 12,240 yuan when he withdrew it. Find the kind of money the depositor deposited interest rate.

(5) The selling price of a certain product after a price reduction of 12% is 176 yuan. Find the original price of the product.

(6) Due to seasonal influence, within a month, the price of a certain product dropped by 10 yuan after increasing by 10 yuan. The current price is 297 yuan. Find the original price of the product.

3. Distribution of materials:

(7) A basket of pears, scattered and packed in small boxes, 8 boxes were used, and 8kg was left that could not be packed; 9 boxes were used , then the last box can still hold 4kg. Find the mass of this basket of pears.

(8) For a school's spring outing, if 13 buses are chartered, then 14 people will have no seats; if one more bus is chartered, there will be 26 more empty seats. What is the total number of people on the spring outing? How much?

4. Proportion issue:

(9) In a certain period, the ratio of Japanese yen to RMB is 25.2:1. So how many RMB can be exchanged for 500,000 Japanese yen?

(10) The length of a certain part on the drawing is 32cm, and its actual length is 4cm. Then measure the length of another part on the drawing to be 12cm. Find the actual length of this part.

(11) A person has planned a salary of 2,600 yuan. The ratio of book purchases, leisure and entertainment expenses, household expenses, and savings is 1:3:5:4. How much does this person plan to spend on leisure and entertainment? Yuan?

5. Deployment issues:

(12) The total number of people in the first workshop and the second workshop is 150. If 15 workers from the first workshop are transferred to the second workshop, the number of people in the two workshops is equal. Find the number of people in the second workshop.

(13) There are 32 workers in workshop A and 62 workers in workshop B of a factory. Now, 98 new workers are recruited from outside the factory and assigned to the two workshops. How should the distribution be done so that the number of workers in workshop B can be increased? The number of people is three times that of a workshop.

6. Number problems:

(14) The sum of three consecutive even numbers is 360. Find these three even numbers.

(15) The sum of a two-digit ones digit and tens digit is 10. If the ones digit and tens digit are exchanged, the new two-digit number obtained is smaller than the original two-digit number. If the number is greater than 18, find the original two digits.

7. Geometric Problems:

(16) Forge a cube iron block with an edge length of 20cm into a rectangular iron block with a length of 100cm and a width of 5cm. Find the rectangular iron block height.

(17) A cube iron block with an edge length of 20cm is submerged into a measuring cylinder containing water. It is known that the bottom area of ??the measuring cylinder is 12cm2. How many centimeters has the middle surface of the measuring cylinder risen?

(18) The supplementary angle of an angle is 42° less than half of the supplementary angle of the angle. Find this angle.

(19) It is known that the supplementary angle of an angle is 10° greater than three times the supplementary angle of the angle. Find the measure of this angle.

8. Sum problem:

(20) The tractor plowed x acres of land on the first day, then ______ acres were left, and it was plowed on the second day If there are 12 more acres left, then ________ acres are plowed the next day, leaving ________ acres.

(21) Li Lei read half of the book on the first day, and the remaining half of 25 pages on the second day, leaving 36 pages unread. If there are *** in the whole book x page, then the number of pages read the next day is represented by

(22) A factory processed a batch of parts. On the first day, 25 more parts were completed. On the second day, 12 less of the remaining parts were completed. On the third day, the remaining parts were completed. 64 pieces, find the total number of parts.

9. Mass fraction problem:

(23) Two alcohols, one with a concentration of 60 and the other with a concentration of 90. Now we need to prepare 300 grams of 70 alcohol, each How much alcohol is needed?

(24) There are two alloys of copper and silver, A and B. Alloy A contains 25 silver, and alloy B contains 37.5 silver. Now we need to melt 100 kilograms of alloy containing 30 silver. Two kinds of alloys. How much of each alloy should be used?

(25) There are a number of 4 salt water. After evaporating some water, it becomes 10 salt water. Then add 300 grams of 4 salt water to mix or turn into 6.4 salt water. Ask the mass of the initially added salt water. .

10. Supporting issues:

(26) There are 42 workers in the packaging factory. Each worker can produce an average of 120 circular iron sheets or 80 rectangular iron sheets per hour. , two round iron sheets and one can be matched into a sealed drum. How to arrange workers to produce round or rectangular iron sheets and assemble the iron sheets reasonably?

(27) There are 28 workers in a workshop producing bolts and nuts. Each person can produce an average of 12 bolts or 18 nuts per hour. How should the workers who produce bolts and nuts be allocated so that the bolts and nuts can be produced? Do the nuts match exactly (two nuts for one bolt)?

11. Clock problem:

(28) Find the time when the hour hand and minute hand of the clock coincide between 5 o'clock and 6 o'clock.

(29) Find the time when the hour hand and minute hand of the clock are in a straight line between 5 o'clock and 6 o'clock.

12. Project Problem:

(30) A project takes 10 days to complete when A does it alone, and 15 days when B does it alone. After the two work together for 4 days, the remaining The next part is done by B alone. How many days will it take to complete?

(31) To complete a certain project, A alone takes 8 days, B alone takes 12 days, and B alone takes 5 days. After the two teams cooperate, how many days can the entire project be completed?