Make up three practical problems according to 2X-4 = 30
① There are two pairs of apples with the same number. After eating 4, there are 30 left. How many apples are there in each pile?
② Xiao Ming has two papers to do, none of which has the same number of questions. Now Xiao Ming has done four questions, and there are 30 questions left. How many questions did each paper have?
③ There are two groups with the same number of people. Four of them left, and there are 30 left. How many people were there in each group?
RELATED INFORMATIONS
- 1. Calculation: (1) (- A ^ 2) ^ 3 (2) (- M) ^ 3) ^ 4
- 2. 100-18 * 3
- 3. Please use the equation of X / 2 + X / 3 + X / 4 = 50 to make up a practical problem related to your own life
- 4. This year, Xiaomin's father's age is five times that of Xiaomin. Eight years later, Xiaomin's father's age is three times that of Xiaomin. How old is Xiaomin today? 2. In the store, apples are 50 kg more than pears. When 5 kg pears are sold, the kilogram more than apples is just half of the kilogram left in pears. How many kilogram of apples and pears are there in the store? Note: if there is a question that cannot be done, please indicate it!
- 5. A 470 meter long train passes the 1030 meter long bridge in 1 minute and 20 seconds, and then passes a tunnel in 40 seconds at the same speed. How long is the tunnel?
- 6. How to set up formulas for the application problems of linear equation of one variable
- 7. A practical problem, a formula, The length of a rectangular wheat field is 100 meters and the width is 60 meters. How many sprinkler irrigation devices are needed if the automatic rotary sprinkler irrigation device with a range of 100 meters is used for sprinkler irrigation?
- 8. If a batch of apples are distributed to the children in two classes, each of them will get 6 apples on average. If they are only distributed to the children in the big class, each of them will get 10 apples on average. If they are only distributed to the children in the small class, how many apples can each of them get?
- 9. Practical questions (formulas and answers) 1. 36 workers, each of whom can process 10 class a parts or 16 class B parts every day. Two class B parts and one class a part form a set. How many people should be arranged to process class a parts and class B parts respectively every day, so that the two parts can be fully matched 2. The sea route from a to B is nearly 40 kilometers than the highway. At 10 a.m., a ship sails from a coastal road to B, and at 1 p.m., a car also sails from a to B along the highway, and arrives at the same time. The ship is 24 kilometers per hour, and the car is 40 kilometers per hour. How long is the highway from a to B
- 10. OK, I'll add a lot of points! 1. There are 270 books on the two bookshelves. Now put 1 / 6 of the books on the first bookshelf into the second bookshelf. At this time, the ratio of books on the two bookshelves is 5:4. How many books are there on each bookshelf? 2. The area ratio of the front, upper and left sides of a cuboid is 7:3:2. It is known that the upper area is 50 square centimeters. What is the surface area of the cuboid?
- 11. What formulas are applied to junior high school practical problems?
- 12. The formula of applied problems in junior algebra For junior high school algebra application problem calculation formula, such as growth rate, interest rate, profit, work problems, travel problems, profit and loss problems Don't worry about geometric theorems
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- 14. A practical problem of grade one in junior high school with a and B In 2007, a farmer contracted several mu of barren hills and invested 7800 yuan to plant 2000 fruit trees. This year, the total output of fruit is 18000 kg. The fruit is sold at a yuan per kilogram in the market and B yuan per kilogram in the orchard (B is less than a). The farmer brought the fruit to the market and sold 1000 kg per day on average, with the help of 8 people. Each person paid 25 yuan per day, and the agricultural vehicle freight and other taxes were 100 yuan per day (1) A and B represent the income from selling fruits in two ways respectively? (2) If a = 1.3 yuan, B = 1.1 yuan, and the two ways of selling fruits sell out all the fruits in the same time, please explain which way is better by calculation (3) The farmer strengthens the management of the orchard and strives to achieve a net income of 15000 yuan by next year. The farmer adopts the better selling method in (2). What is the growth rate of net income? (net income = total income total expenditure)
- 15. How to get the result of a: B from (B-A): a = a; b
- 16. A-b-a-b
- 17. Calculation questions a, B, C a+bc^2=30, a+bc^3=50, a+bc^4=90 Find a, B, C How to get it?
- 18. (b-c)(b+c-a)+(c-a)(c+a-b)+(a-b)(a+b-c) It is related to factorization
- 19. A plane flies 240 meters per minute, B flies 15 minutes, C flies 3600 meters in total
- 20. A group of parts processed by four persons of a, B, C and D A processes frac12;, B processes 3 / 1 of the rest, C processes 5 / 3 of the rest, and D processes 200 pieces. How many parts are there in total? Please be clear