2. The school library was relocated, with 6.5438+0.5 million copies. It was originally planned to arrange a group of students to help move books in the labor class of a class every day, and 6.5438+0.8 million books were moved in two days. If the books are required to be moved within 7 days, assuming that each group moves the same books, how many groups will be arranged to move books every day in the next few days?
Someone asked the teacher how many students there were in his class. The teacher said, "Half of the students are studying math, one quarter are studying music, one seventh are studying foreign languages, and there are no more than six students playing football on the playground." How many students are there in this class?
4. The school has allocated several dormitories to the seventh grade girls. If there are five people in each dormitory, the remaining five people will have no place to live. If there are eight people in each dormitory, one room is empty and one room is not satisfied. It is understood that there are less than 35 girls in this grade. How many girls are there?
Students in Grade Two of our school need to rent some buses to organize a spring outing. If you rent more than 30-seat buses, when all of them are full, there are still 10 people left. If you take bus number 45, rent two less, and the first few are full. There are less than 20 seats left in the last carriage. Want to know 200 yuan's pension for 30 buses every day. The rent for 45 seats is 240 yuan. If you rent only one kind of car, which one is cheaper?
6. An engineering team recruits two types of workers 150, knowing that A's monthly salary is 800 yuan and B's monthly salary is 1000 yuan. Now the number of workers in B and B is required to be no less than twice that of A. When asked how many workers A and B employ,
Can recruitment make the construction team pay the least salary?
7. Company A deals in two commodities, A and B. The purchase price of each commodity is 6.5438+0.2 million yuan, and the price is 6.5438+0.45 million yuan. The purchase price of each B commodity is 80,000 yuan, and the selling price is 654.38+10,000 yuan. Their purchase price and selling price remain unchanged. Now it is planned to purchase 20 pieces of Party A and Party B * * *, with the use capital of not less than 6.5438+0.9 million yuan and not more than 2 million yuan.
1 What kinds of purchasing schemes does the company have?
What kind of purchasing scheme can the company adopt to obtain the maximum profit? What is the maximum profit?
If you buy again with the profit obtained in 2, please write down the purchase plan and get the maximum profit directly.
8. During the May Day holiday, a school organized students to travel. If several 45-seat buses are rented separately, they are just full. If you rent only 60 buses, there will be 30 seats left without 1 group. It is known that 45-seat passenger cars are rented in 250 yuan, while 60-seat passenger cars are rented in 300 yuan. In order to save rent and ensure that every student has a seat, it is decided to rent two kinds of buses at the same time, so that the total number of car rentals can be less than that of renting 45 buses alone. How many cars can be divided into 45-seat buses and 60-seat buses to minimize the rent?
9. Many students live in several dormitories. If there are four students in each room, it is impossible to arrange 20 people. If there are eight students in each room, then a dormitory is not empty and dissatisfied. Please ask about the number of dormitories and students.
10. A basket of apples was distributed to several students. If each student is divided into four, there are three left. If each student is divided into six parts, the last student can only get two apples. Find the number of students and the number of apple trees.
1 1. A plant is suitable for growing on the hillside of 16-20 degrees Celsius. It is known that the temperature drops by 0.55 degrees Celsius per 100 meters above sea level in mountainous areas, and now the average temperature at the foot of the mountain is 22 degrees Celsius. So which part of the mountain is suitable for growing this plant locally?
12. Give some students a basket of apples. If each student gets four apples, there are nine left. If each student gets six apples, the last student will get less than three apples. Find out the number of students and apples.
13. Our city is the most primitive tilapia culture area, and the advantages listed by the Ministry of Agriculture as tilapia culture have disappeared. A farm plans to raise pollution-free standardized tilapia and grass carp for one year, and the total output g (ton) of these two species is required to meet the following requirements: 1580≤G≤ 1600, and the total output value100000 yuan, which is known to be related. ask
What range should Robbins' output be controlled in the second half of this farm? (output value = output × unit price)
14. In order to protect the environment, an enterprise decided to buy 10 sets of sewage treatment equipment. There are two types of equipment, A and B. The price, monthly sewage treatment capacity and annual consumption fee of each equipment are as follows:
Type a and type b
Price (ten thousand yuan/set) 12 10
Sewage treatment capacity (ton/month) 240 200
Annual consumption expense (ten thousand yuan/set) 1 1
According to the budget, the funds used by enterprises to purchase equipment are not higher than 6.5438+0.05 million yuan.
(1) Please design several purchasing schemes for this enterprise;
(2) If the amount of sewage produced by an enterprise is 2,040 tons per month, which procurement scheme should be chosen to save money;
(3) Under the condition of (2), if the service life of each equipment is 10 year, and the sewage treatment fee of the sewage plant is per ton 10 yuan, please calculate how much ten thousand yuan the enterprise will save by treating the sewage by itself compared with discharging the sewage to the sewage plant. (Note: Enterprise sewage treatment expenses include equipment purchase expenses and consumption expenses)
15. A mountain school in our city arranged accommodation for some students who were far away from home and transformed some classrooms into several houses. If there are 5 people in each room, 12 people can't arrange it; If there are 8 people in each room, there are some beds left in one room. How many rooms can the school arrange for students to stay? How many students can you accommodate?
16. The ticket for a garden is 10 for one-time use. Considering people's different needs, and in order to attract more tourists, the garden not only keeps the original way of selling tickets, but also introduces the way of "purchasing individual annual tickets" (individual annual tickets can be used by ticket holders for one year from the date of purchase). Annual tickets are divided into three categories: Class A annual tickets are each 120 yuan, and ticket holders do not need to purchase tickets when entering the park; Class B tickets for each 60 yuan. You need to buy a new ticket to enter the park with a ticket, and go to 2 yuan every time; Class C tickets for each 40 yuan. When ticket holders enter the park, they need to buy another ticket for each 3 yuan. (1) If you only choose one way to buy tickets, and you plan to spend 80 yuan to buy tickets for the garden every year, then try to find out the way to buy tickets that will make you enter the garden the most times through calculation. (2) It is more cost-effective to enter the park at least several times a year and buy a class A annual ticket.
17. Xiao Wang wants to decorate his home. He went to the store to buy lamps. There are 100 watt incandescent lamps and 40 watt energy-saving lamps in the store. Their unit prices are 2 yuan and 32 yuan respectively. It is known that the lighting effect and service life of these two lamps are the same. It is understood that the electricity price of Xiao Wang's house is 0.5 yuan per kilowatt hour. Excuse me, when the service life of these two lamps exceeds how long, is it cost-effective for Xiao Wang to choose energy-saving lamps? [Electricity consumption (degrees) = power (kilowatts) × time (hours).
18. At present, it is planned to transport 1240 tons of Class A goods and 880 tons of Class B goods to a certain place by truck. It is known that this truck is hung on 40 trucks with different specifications. The cost of using A-class cars is 6000 yuan, and the cost of using B-class cars is 8000 yuan.
(1) Assuming that the total cost of transporting this batch of goods is 10000 yuan, this truck has X A-cars. Try to work out the formula that the number of vehicles x represents the total cost y.
(2) If each A-type vehicle can armor up to 35 tons of Class A goods and 15 tons of Class B goods, and each B-type vehicle can armor up to 25 tons of Class A goods and 35 tons of Class B goods, what are the plans for arranging vehicles according to this requirement?
19. A city produces an average of 700 tons of garbage every day, which is treated by two garbage treatment plants, A and B. It is known that Factory A treats 55 tons of garbage every hour at the cost of 550 yuan; Factory B can handle 45 tons of garbage per hour at the cost of 490 yuan. (1) How many hours does it take for Factory A and Factory B to treat the garbage in this city at the same time? (2) If it is stipulated that the daily cost of garbage disposal in this city should not exceed 7370 yuan, how many hours does it take for a factory to dispose of garbage every day?
20. The price of Type A refrigerator in a shopping mall in our city is 2 190 yuan, and the daily power consumption is 1 kW. Recently, the shopping mall brought back a batch of B-type refrigerators, the price of which was 65,438+00% higher than that of A-type refrigerators, but the daily power consumption was 0.55 kW. In order to reduce inventory, the mall decided to sell Type A refrigerators at a reduced price. Please answer the following questions: (65 (2) If only the price and power consumption are considered, is it cost-effective for consumers to buy Type A refrigerators when some shopping malls discount the price of Type A refrigerators at least several times? (The service life of both refrigerators is 10 year, 365 days per year, and the electricity charge per kilowatt hour is calculated in 0.4 yuan).
It is unfair to hope to adopt it.