Ask for 80 math and arithmetic questions

The solution set of the inequality axgt; a is The annual profit increased by 1 million yuan, and the per capita profit increased by at least 6,000 yuan. What was the minimum profit of the entire factory the year before last?

. In the "Me and the Olympics" knowledge competition, there are 20 questions. Each question is worth 10 points for a correct answer. 5 points will be deducted for wrong answers or no answers. How many questions must Li Ming answer correctly at least? , the score is no less than 80 points

Xiao Ming’s mother took 100 yuan to the supermarket for shopping. She spent 50 yuan to buy bedding and 30 yuan to buy Xiao Ming’s schoolbag. If she bought another 3 kilograms of bananas , then the money she brought is not enough; if she buys another 2.5 kilograms of bananas, there is still money left. If the unit price of bananas is an integer, verify the unit price of bananas.

(1) In order to welcome 2008 In the city women's football competition in 2018, the Municipal Football Association held a football match. The points rules and reward plan are as follows: Win one, draw one, lose one

1. Several children in the kindergarten share a box of apples. If each If each person is divided into 3 apples, there will be 7 apples left; if each person is divided into 5 apples, then one person will get less than 5 apples. How many children are there? How many apples

After market research, a company found that the output value of each product of product A is 450,000 yuan, and the output value of each product of product B is 750,000 yuan. These two products are required to be updated throughout the year. The output is increased by 20 pieces, and the total output value of these 20 pieces P (ten thousand yuan) satisfies: 1100lt; Plt; 1200, then how should the company arrange the production of two products, A and B tomorrow?

A company passed According to market research, the output value of each product of product A is 450,000 yuan, and the output value of each product of product B is 750,000 yuan. It is required that these two products produce 20 new products throughout the year. The total output value of these 20 products is P. (10,000 yuan) meets: 1100lt; Plt; 1200, then how should the company arrange the production of products A and B tomorrow?

The monthly water bill for Xiaofangjia is not less than 15 yuan, and the water company Regulations: If each household uses less than 5 cubic meters of water per month, the charge will be 1 or 8 yuan per cubic meter. If each household uses more than 5 cubic meters of water per month, the excess will be charged 2 yuan per cubic meter. The minimum water consumption for small households is How many

1. Use an A-type water pump that can pump 1.1 tons of water per minute to pump out the pool water. It can be pumped out in half an hour. If you use a B-type water pump, it can be pumped out in 20 to 22 minutes. How many tons more water does Type B pump pump than Type A pump?

2. The instruction manual of a medicine says: "Daily dosage 60-120 mg, divided into 3-4 times." What is the range of dosage for taking this medicine at one time?

The instruction manual of a medicine says: "Daily dosage 60~120mg, taken in 3~4 times." What is the range of dosage for one dose?

Mathematics Book P58-59, 17, 18, 19, 20 questions, P89, 16, 18 questions,

1. Rewrite ( ) into a number with "ten thousand" as the unit, which is 95.678 million, omit "100 million" The mantissa behind " is approximately ( ).

2. Saw the 5-meter-long steel bar into small sections of the same length, and saw it 6 times. Each section accounts for ( ) ( ) of the total length, and each section is ( ) meters long. If it takes 2 minutes to saw into two sections, it will take () minutes to saw into 6 sections.

3. Observation and thinking:

(1) □ and △ in the formula each represent a number. It is known that: (△ □)×0.3=4.2, □÷0.4=12.

Then, △ = ( ), □ = ( ).

(2) Observe the picture on the right and fill in a letter in the brackets below to make the equation true.

Front area ( ) = Top area ( )

4. The picture on the right shows the number of days it takes three people A, B, and C to complete a certain project alone

Statistical chart. Please look at the picture and fill in the blanks.

① If A and B cooperate, this project can be completed in ( ) days.

② A will do the work for 3 days first, and C will do the rest of the work. It will take ( ) days to complete.

5.a=2×3×m, b=3×5×m (m is a natural number and m≠0), if the greatest common divisor of a and b is 21,

then m is ( ), and the least common multiple of a and b is ( ).

6. Divide a rope into 5 strands and 6 strands respectively. If the 5 strands are 20 cm longer than the 6 strands, then the length of the rope is () meters.

7. The average of the three numbers A, B and C is 70, A: B = 2:3, B: C = 4:5, B’s number ( ).

8. The decimal point of a number is first moved one place to the right, and then three places to the left. The resulting new number is 34.65 less than the original number, and the original number is ( ).

9. Using "ten thousand" as the unit, the maximum difference between the exact number of 50,000 and the approximate number of 50,000 is ( ).

10. Xiao Ming bought a new bottle of toothpaste with a net volume of 45 cubic centimeters. The diameter of the circular outlet of the toothpaste is 6 mm. He brushes his teeth once in the morning and evening, and each time he squeezes out about 20 millimeters of toothpaste. This bottle of toothpaste is estimated to last ( ) days. (Take 3 as the approximate value of pi)

11. When deriving the area formula of a circle, divide the circle into several equal parts and form an approximate rectangle. It is known that the length of the rectangle is 6.42 cm longer than the width. The area of ??a circle is ( ) square centimeters.

12. A ship sails 30 kilometers per hour from point A to point B, and then returns along the same route. If the average round-trip speed is 40 kilometers, it should sail per hour when returning ( )km.

2. Repeated comparison, selection of the best: (10)

1. Known: a×23 = b×135 = c÷23, and neither a, b nor c are Equal to 0, then the smallest number among a, b, and c is ( ).

① a ② b ③ c

2. In the integer division formula with remainder, the divisor is b and the quotient is c, (neither b nor c is 0), the dividend is the largest for( ).

① bc＋b ② bc-1 ③ bc＋b-1

3. In the brine containing 30% salt, add 6 grams of salt and 14 grams of water. At this time, the salt content of the brine is ( ).

① Equal to 30 ② Less than 30 ③ More than 30

4. Xiaohua wants to help her mother do the following things on weekends: it takes 20 minutes to wash clothes in the washing machine; it takes 6 minutes to sweep the floor ; It takes 10 minutes to wipe the furniture; it takes 5 minutes to dry the clothes. After reasonable arrangements, it will take at least ( ) minutes for her to complete these things.

① 21 ② 25 ③ 26

5. Among the following formulas (neither a nor b is 0), a and b are inversely proportional to ( ).

① a×8＝b5 ② 9a＝6b ③ a×13 -1÷b= 0 ④ a＋710＝b

6. Give all 5 identical gifts to 3 Have children, so that each child can receive a gift. There are ( ) different ways to distribute gifts.

① 3 ② 4 ③ 5 ④ 6

7. If a pair of shoes is sold for 140 yuan, you can earn 40, if you sell a pair of shoes for 120 yuan, you can earn ( ).

① 20 ② 22 ③ 25 ④ 30

8. On a map with a scale of 1:30000000, the distance from point A to point B is 5.6 cm. A car According to the ratio of 3:2, the entire distance is traveled in two days. The distance difference between the two days is ( ) kilometers.

① 672 ② 1008 ③ 336 ④ 1680

9. If the height of a cone remains unchanged and the base radius increases by 13, the volume will increase ( ).

① 13 ② 19 ③ 79 ④ 169

10. A car drives from point A to point B 80 kilometers away at a speed of 50 kilometers per hour.

The gasoline you bring can last up to 2 hours. If you don’t refuel on the way, in order to ensure that you can return to the starting point, you should drive back after driving at most ( ) kilometers.

① 20 ② 40 ③ 50 ④ 100

3. Read the question clearly and calculate cleverly:

⑴ Write the number directly and it is fast! (8)

1322-199= 1.87 5.3= 2.5×2.4= 1÷13 -13 ÷1 =

4.9×8.1≈ 23.9÷8≈ 0.32 - 0.23 = ( ) ：17 = 17

⑵ The calculation is meticulous and clever! (Write the simplified calculation process) (12)

2004×20022003 (115 +217)×15×17 11×2 12×3 13×4… 198×99 199×100

Relax your wrist, collect your thoughts, and turn to the next page!

⑶ Solving equations, I have no problem! (9)

4÷23 Innovation

You must be familiar with the following graphics, so please take action and success belongs to you!

⑴ There are 12 cube products of 1 cubic decimeter. Please design a rectangular parallelepiped packaging box for it. ***There are ( ) kinds

Different packaging methods; when packaging When the length of the box is ( ) decimeters, the width is ( ) decimeters, and the height is ( ) decimeters,

Wrapping paper can be saved the most. At least ( ) square decimeters of wrapping paper are required (the joints are ignored). (5)

⑵ The diameter of the street garden is 5 meters. Now a 1-meter wide ring road is built around it. Please draw the design according to the scale of 1250

and Find the actual area of ??the road surface. (3+2)

Calculate as o.

Calculation

(3) The side length of the small square table top is 1 meter. If you spread out its four sides, it will be I made a round tabletop (as shown below).

Find the area of ??the circular tabletop. (3)

Part 3: Entering life and solving problems

There are many problems in life related to mathematics. Can you solve these problems? I believe you can do it!

1. Just list the formula without calculation: (8)

① Xiao Ming spent 8 days reading a book, and read 19 pages of the book every day and 2 more pages. How many pages does this book have?

Column formula:

③Two cars A and B travel towards each other from two places at the same time. Car A travels 45 kilometers per hour, and car B travels 42 kilometers per hour. The two cars met 12 kilometers from the midpoint. How many hours have passed since the two cars drove out at the same time before they met?

② A newspaper, if subscribed once a month, there is no discount and it costs 10 yuan. If you subscribe once a year, you can get a discount of 10%. How much does it cost to subscribe for a year?

Column formula:

④ A shopping mall participated in property insurance, with an insurance amount of 40 million yuan and an insurance rate of 0.75. Due to the accident, the value of the lost items reached 6.5 million yuan. The insurance company If the compensation is 5 million yuan, how many thousands of yuan will the mall actually lose?

Column formula: Column formula:

2. Look at the diagram and calculate the formula: (5)

3. For the health and safety of students, the school gives each Boarding students are provided with a water cup, each water cup costs 3 yuan, Ocean Mall offers a 10% discount, and Parkway Mall offers "buy eight and get one free". The school wants to buy 180 water cups. Please be your "consultant" and do the math: Which store is more cost-effective? Please write down your reasons. (5)

4. In a two-layer bookshelf, the upper layer contains 18 more books, three times as many as the lower layer. If 101 books are taken out from the upper layer and placed on the lower layer, then the two layers will contain 18 books. The number of books is equal.

How many books are there on each floor? [Use equations to solve] (5)

5. A school student holds a tour. If a 45-seat bus is rented, 15 people will have no seats. If the same number of 60-seat buses is rented, one bus will be empty. car. It is known that the rental price of a 45-seater bus is 220 yuan and the rental price of a 60-seater bus is 300 yuan.

Question: ⑴ How many students does this school have at a time? (3) ⑵ What is the most economical way to rent a car? (2)

Points 3 1 0

Reward 1500 700 0

When the game reaches the end of 12 rounds (each team needs to play 12 games) , Team A scored 19 points. If there is one game per game, each participating team member will receive an appearance fee of 500 yuan. Suppose team A wins X games and loses Z games, and the total income of one participating player from bonuses and appearance fees is W yuan. 1. Write the relationship between Z and X. 2. Write the relationship between W and How much is it?

If you use an A-type water pump that can pump 1.1 tons of water per minute, it can be pumped out in half an hour; if you use a B-type water pump, it can be pumped out in an estimated 20 to 22 minutes. How much more water can be pumped per minute by Type B water pump than Type A water pump?

The selling price of a certain product is 150 yuan. The profit a merchant can make by selling one such product is 10-20 yuan of the purchase price. What is the price range (accurate to 1 yuan)?

The purchase price of apples is 1.5 yuan per kilogram. There is an estimated 5 percent normal wear and tear on apples sold. What is the minimum price a merchant can set to avoid losing money?

When blasting in a mine, in order to ensure safety, after igniting the fuse, move to a safe area 300m away before blasting. The burning speed of the fuse is 0.8m/s, and the person leaving speed is 6m/s. Asking how much m is required for the fuse?

The factory had 280 employees the year before last. Last year, 40 employees were reduced after structural reform. The annual profit of the whole factory increased by 1 million yuan, and the per capita profit increased by at least 6,000 yuan. The annual profit of the whole factory the year before last At least how much?

After lighting the fuse, workers must move to a safe area 400m away before blasting. The burning speed of the fuse is 1cm/s, and the worker's transfer speed is 5m/s. How many meters longer should the fuse be?

In order to develop new products, a beverage factory used 19 kilograms and 19 kilograms of two kinds of juice raw materials A and B each to trial-produce two new types of beverages A and B, 50 kilograms respectively. The following is the relevant data of the test:

A new type of beverage contains 0.5 A and 0.2 B per kilogram.

New type B beverage contains 0.3 A and 0.4 B per kilogram.

1 .Assume that x kilograms of beverage A need to be prepared, list the set of inequalities that satisfy the meaning of the question, and find the solution set.

2. The cost per kilogram of beverage A is 4 yuan, and the cost per kilogram of beverage B is is 3 yuan. Based on the calculation result of 1., determine how many kilograms of beverage A and B are prepared, and the total cost of the two beverages A and B is the smallest?

The students took a group photo and printed two for a fee of 5.7 yuan. , an additional print costs 0.96 yuan, and each person is scheduled to pay no more than 2 yuan on average, and each person will get a photo. How many students are there at least participating in the photo shoot?

In the donation activity for the "Project Hope" of Grade 9 classes A and B of Guangming Middle School, the two classes donated the same total amount, more than 300 yuan and less than 400 yuan. It is known that one person in class A donated 6 yuan, and everyone else donated 9 yuan; one person in class 1 donated 13 yuan, and everyone else donated 8 yuan. The total number of students in Classes A and B is *** small.

There are 6 cubic meters of water at 18 degrees Celsius in the container. Now we need to pour 8 cubic meters of water into it so that the temperature of the water mixed in the container is not lower than 30 degrees Celsius, and not Above 36 degrees Celsius, what should be the temperature range of the 8 cubic meters of water injected?