Searching for 200 mixed operations of rational numbers

Searching for 200 mixed operations of rational numbers

1.2100-21×53+2255
2.(103-336÷21)×15
3.800-(2000-9600÷8)
4.40×48-(1472+328)÷5
5.(488+344)÷(202-194)
6.2940÷28+136×7
7.605×(500-494)-1898
8.(2886+6618)÷(400-346)
9.9125-(182+35×22)
10.(154-76)×(38+49)
11.3800-136×9-798
12.(104+246)×(98÷7)
13.918÷9×(108-99)
14.(8645+40×40)÷5
15.(2944+864)÷(113-79)
16.8080-1877+1881÷3
17.(5011-43×85)+3397
18.2300-1122÷(21-15)
19.816÷(4526-251×18)
20.(7353+927)÷(801-792)
21.(28+172)÷(24+16)
22.6240÷48+63×48
23.950-28×6+666
24.86×(35+117÷9)
25.2500+(360-160÷4)
26.16×4＋6×3
27.39÷3＋48÷6
28.24×4－42÷3
29.7×6-12×3
30.56÷4＋72÷8
Practical questions:
1. Mother bought back 3 kg cauliflower, she paid 5 yuan, recovered 0.5 yuan, how much yuan per kg cauliflower?
2. There are 50 story books in class 51, which is twice as many as the art books. How many art books are there?
3. A piece of triangle land, the area is 280 square meters, the bottom is 80 meters, how many meters is the height?
4. A trapezoid has an area of 450 square meters, a height of 30 meters, a top bottom of 15 meters, and a bottom of how many meters?
5. There are 80 sheep on the hillside, of which the white sheep is four times of the black sheep. How many are the black sheep and the white sheep on the hillside?
6. Two baskets of oranges were sold in the store. The first basket weighs 26 kg, and the second basket weighs 29 kg. The second basket costs 9 yuan more than the first basket. How much is the average per kilogram of oranges?
7. A trapezoidal wheat field, with an area of 540 square meters and a height of 18 meters, has a top bottom of 20 meters and a bottom of how many meters?
8. Car a and car B leave 750 kilometers apart at the same time. They run in opposite directions and meet each other in 5 hours. Car a runs 80 kilometers per hour, and car B runs how many kilometers per hour?
9. After driving for 4.5 hours, car a landed 13.5 kilometers behind car B. It is known that car a travels 35 kilometers per hour, and how many kilometers per hour does car B travel?
10. It is known that Party A processes two more parts per hour than Party B. how many of these parts are there in total?
11. The stadium bought 16 basketball and 12 football, and paid 760 yuan in total. It is known that the unit price ratio of basketball and football is 5:6. How much do the stadium pay for basketball and football
12. When a shop buys a batch of leather sandals, the selling price of each pair is 15% higher than the purchase price. If it sells all of them, it will make a profit of 120 yuan. If it only sells 80 pairs, the difference is 64 yuan. How much is the purchase price of leather sandals?
13. Master Zhang wants to make a cylinder with two pieces of iron sheet (see the figure below). He chooses one piece to cut out two bottom surfaces, and then uses the other piece to make the side surface. It is required that the volume of the cylinder made by Master Zhang should be as large as possible. What is the surface area and volume of the cylinder made by Master Zhang? (regardless of the joints, π takes 3.14)
14. A goes from the east city to the West City, 5 kilometers per hour. B goes from the west city to the east city, 4 kilometers per hour. If B starts one hour earlier than a, then they just meet in the middle of the two cities. How many kilometers is the distance between the East and the West cities?
15. A business company has two warehouses to store color TV sets. The storage ratio of warehouse A and warehouse B is 7:3. If 30 TV sets are transferred from warehouse A to warehouse B, the ratio of warehouse A and warehouse B is 3:2. How many TV sets are stored in these two warehouses?
16. It takes 10 hours for an express train to drive from city a to city B, and 15 hours for a local train to drive from city B to city A. the two trains leave each other at the same time. When they meet, the express train travels 120 kilometers more than the local train. How many kilometers are there between the two cities?
17. There are 5 tractors, and the cultivated land is 12000 mu in 24 days. How many tractors need to be added after 54000 mu in 18 days?
18. In a square banana garden with a side length of 84 meters, the spacing of banana trees is 2 meters and the row spacing is 8 meters. If each banana tree receives 65 kg of banana fruit and 0.45 yuan per kg, how much yuan can the banana garden earn in a year?
19. The transport rate of Dongfeng truck is 2.5 times that of tractor, and that of large container truck is 2.5 times that of Dongfeng truck
It takes six hours to transport a pile of goods by Dongfeng truck. If we use a tractor to transport half of the goods,
How many hours does it take to transport the other half in a large container truck?
20. Party A and Party B sell eggs. Party A has 10 more eggs than Party B, but the income after all sales is 15 yuan. If Party A's eggs can be sold for 18 yuan at the price of Party B, how many eggs do Party A and Party B have?