2. There is a two-digit number, and the unit number is 5 larger than the ten-digit number. If the positions of these two numbers are reversed, the sum of the new number and the original number is 143. Find this two-digit number.
Last year, the total income of the school-run factory was 500,000 yuan more than the total expenditure. This year, the total revenue increased by 65,438+00% compared with last year, and the total expenditure was saved by 20%, so the total revenue was 654.38+00 million yuan more than the total expenditure. Find the total income and total expenditure of last year.
4. Party A and Party B are in place A, and Party C is in place B. The three of them set out at the same time. Party A, Party B and Party C walk in opposite directions, with Party A walking 120m, Party B walking 130m and Party C walking 150m. It is known that after C meets B, it will take another 5 minutes to meet A and find the distance between A and B. ..
5. The following table shows the daily closing price per share of A and B shares in a certain week (closing price: the price of stocks at the end of daily trading):
Monday Tuesday Wednesday Thursday Friday
A 12 yuan 12.5 yuan 12.9 yuan 12.45 yuan 12.75 yuan.
B 13.5 yuan 13.3 yuan 13.9 yuan 13.4 yuan 13.75 yuan.
Some people hold a large number of A shares and B shares this week. If calculated according to the daily closing price of two stocks (excluding fees, taxes, etc. ), his account will be increased by 200 yuan last Tuesday, and by 1.300 yuan on Wednesday. How many shares does this person hold in A and B respectively?
6. Someone has deposited 8,000 yuan in two forms, one is * * *, in which the annual interest rate of A's deposit is 10% and the other is 12%. After one year, the interest of * * * is 860 yuan. How much do A and B deposit?
7. The mall plans to allocate 90,000 yuan to buy 50 TV sets from manufacturers. It is known that this manufacturer produces three different models of TV sets, and the appearance prices are 1500 yuan, 2 1000 yuan each and 2,500 yuan each.
(1) If the shopping mall buys 50 TV sets of two different models at the same time, and it costs 90,000 yuan, please study the shopping plan of the shopping mall;
(2) If a shopping mall sells a first-class TV set, it can make a profit 150 yuan, a second-class TV set can make a profit in 200 yuan, and a third-class TV set can make a profit in 250 yuan. In the scheme of buying two different TV sets at the same time, which purchase scheme should be chosen to get the maximum profit when selling?
8. A new four-story teaching building was built in a middle school. There are 8 classrooms on each floor and 4 doors in and out of the building. The two front doors are the same size and the two side doors are the same size. During the security check, four doors were tested: when one main entrance and two side doors were opened at the same time, 560 students could pass in 2 minutes; When a main entrance and a side door are opened at the same time, 800 students can pass in 4 minutes.
(1) How many students can pass through a main entrance and a side door every minute on average?
(2) During the inspection, it was found that the efficiency of going out would be reduced by 20% due to the crowded students in an emergency. According to the safety inspection, in case of emergency, the students in the whole building should be evacuated safely through these four doors within 5 minutes. Suppose that each classroom in this teaching building has a maximum of 45 students. Q: Do these four doors meet the safety requirements? Please provide a justification for the answer.
9. There are two types of bonds, A and B, with annual interest rates of 65,438+00% and 65,438+02% respectively. The existing 400 yuan bonds will be profitable in 45 yuan after one year. How much are the two bonds? (6 points)
10. There are three kinds of packaging for a beverage, and 1 medium bottle is 20 cents cheaper than 2 small bottles, and 1 large bottle is 40 cents more expensive than 1 small bottles, and it costs 1 9 cents to buy large and medium bottles. How much is each bottle of three kinds of packaged drinks? (6 points)
1 1. A class of students went to Beishan 18km for an outing. There is only one car, so it needs to be divided into two groups. Group A takes the bus first, and Group B walks. When the bus arrives at A, Group A gets off and walks, and the bus returns to Group B. Finally, the two groups arrive at Beishan Station at the same time. Given the speed of 60 km/h and the walking speed of 4 km/h, find the distance from point A to Beishan Station. (6 points)
Reference answer
1.39;
2.49;
32 million yuan; 1.5 million yuan;
4.37800 meters;
5. 1000 shares; 1500 shares;
6.x=5000，y = 3000
7.( 1) Set X Class A TV sets and Y Class B TV sets ... Solution: x = 25y=25.
So the first purchase plan is to buy 25 TV sets of model A and model B..
(2) Set X Class A TV sets and Z Class C TV sets ... Solution: x = 35z= 15.
Therefore, the second procurement plan is to purchase 35 Class A TVs and 15 Class C TVs. ..
(3) Set up B-type Y TV and C-type Z TV. Solution: y = 87.5Z=-37.5 is irrelevant, so it is discarded. So this scheme is not feasible.
(2) The above-mentioned first scheme can make a profit: 150× 25+200× 25 = 8750 yuan;
The second scheme can make a profit:150× 35+250×15 = 9000 yuan;
Because 8750
8.( 1) Suppose a main entrance can pass X students per minute on average, and a side door can pass Y students per minute on average. The system of equations can be obtained from the meaning of the question (omitted): x =120; y=80
A: A little.
(2) The maximum number of students in this building is 4×8×45= 1440.
Four doors can pass 5× 2 (120+80) (1-20%) =1600 people in a crowded place in 5 minutes.
∵ 1600 & gt； ∴ 1440, four doors meet the safety specifications.
A: A little.
9. Let A of X element and B of Y element get X = 150 and Y = 120.
10. Set the unit price of large bottle as X yuan, medium bottle as Y yuan and small bottle as Z yuan. x = 5； y = 3； z= 1.6
1 1. Let A be x kilometers away from the starting point, and the car will return from A to Y kilometers and meet Group B. x =16; y = 14； A It's 2 kilometers from Beishan Station.