6 points for each of the following questions, *** 120 points.
1, calculation:1÷ 50+2 ÷ 50+...+98 ÷ 50+99 ÷ 50 =.
2. The calendar of June 5438+ 10 in 2009 is as shown in the figure, so Children's Day in 2009 is a week.
3. The book "Hope Cup Math Ability Training Course (Grade Four)" has 160 pages, and the number "2" * * * appears twice in its page number.
4. Write the 35 natural numbers 1 to 35 together continuously, which is enough to form a large number:1234567891001... 33435, then the digits of this large number are.
In a math test, all the students in Class 4 (2) scored an average of 88 points, 92 points for boys and 82 points for girls, so the number of boys is twice that of girls.
6. Figure 3 shows the famous Hanoi Tower, which has three disks, which are sleeved on the A-pillar from top to bottom according to the radius from small to large. To move the three disks on the A-pillar to the C-pillar (you can use the B-pillar for transition), it is stipulated that only one disk can be moved at a time, and the big disk cannot be on the small disk, at least once.
7. There is a triangle in the picture.
8. As shown in the figure, the four sides of the quadrilateral ABCD extend by one section respectively, and ∠ CBE, ∠ Bah, ∠ ADG and ∠ DCF are obtained, then the sum of these four angles is equal to.
9. If G(a) is used to represent the divisor of natural number A, for example, there are 1, 2, 3, 6 and * * 4 divisors of natural number 6, denoted as G(6)=4, then G(36)+G(42)=.
10. There are 100 Fuwa in the kitchen window of the Olympic commodity exhibition hall, from left to right:
According to this rule, the 30th place is.
1 1. In the formula shown in the figure, if the same Chinese character represents the same number and different Chinese characters represent different numbers, then number+learning+competition+competition = or.
12. Starting from home, Xiao Ming runs 350 meters to point A in 30 northeast, 200 meters to point B in 30 northwest, and 350 meters to point C in 30 southwest. At this time, Xiao Ming has been one meter away from home.
13. I hope there are dragonfly and cicada spiders in the biological specimen room of primary school *** 1 1. They have 74 legs and 10 pairs of wings. As can be seen from the picture, there is a spider in the specimen room.
14, the average number of human hair is120,000. If it does not exceed 200,000 at most, at least130,000 people in China have the same number of hairs.
15, Dabao and Beckham leave for the city library at the same time. Dabao came back, borrowed books from the library for half an hour, and then rode back to school along the same road, where he met Beckham. The departure time and meeting time of the two are shown in the figure, so the distance between the school and the city library is () meters.
16, abcd, ABC, AB and A represent four digits, three digits, two digits and one digit in turn.
And ABCD-ABC-AB-A = 1787, four-digit abcde= or.
Before the final of 17 and 100 meters, Xiao Fang predicted the ranking of five athletes, and the result of the competition was completely different from her prediction. From the figure 10, we know that the player predicted by Xiao Fang to be the first is actually ranked first.
The area of "windmill" (shaded part) in 18 and 1 is equal to.
19 as shown in figure 12, if a square with a side length of 4cm covers a part of a square with a side length of 3cm, the area difference of the blank part is equal to.
12
a
B
1
c
d
m
1 1
n
20. In the nine squares of figure 13, if the sum of three numbers on each diagonal is equal, then a+b+c+d=
Title number
1
2
three
four
five
six
seven
eight
nine
10
answer
99
one
36
6 1
1.5
seven
35
360
17
english-english
Title number
1 1
12
13
14
15
16
17
18
19
20
answer
24; 28
200
four
6500
10350
2009; 20 10
five
four
seven
29
1, the decimal point of a decimal point moves to the right and left respectively, and the difference between the two numbers is 2.2, then the decimal point is expressed as a fraction.
2. Price of a leather coat 1.650 yuan. If you sell it at a 20% discount, you can still make a profit 10% (relative to the purchase price). If it is sold at the price of 1650 yuan, it can make a profit in RMB.
3. Find the number11...1(2000) 222 ... 22 (2000) 333 ... 33 (2000) is represented by the number 333 ... 33 (2000).
4. Calculate (1/(1× 2)+2/(/kloc-0 /× 2× 3)+3/(/kloc-0 /× 2× 3× 4)+...+9/(1)
5. The speed of a ship sailing downstream is 30 km/h, and it is known that the voyage of sailing downstream for 3 hours is equal to the voyage of sailing upstream for 5 hours, so the voyage of this ship drifting downstream 1 hour is () km.
6. A TV factory plans to produce 15 sets 1500 sets. As a result, after five days of production, the TV factory has improved its production efficiency by 25% due to the introduction of a new production line, and will complete the plan () days ahead of schedule.
7. Choose three numbers from 1, 2, 3, 4, 5, 6, 7, 8 and 9 to make the sum even, then * * * has () different selection methods.
8. The page numbers of a book are consecutive natural numbers 1, 2, 3, 4, …9, 10… When adding up these page numbers, someone adds one of the page numbers incorrectly twice, and the result is 200 1, so the book has () pages.
9. There are 2 1 flower distributed to 5 people. If the number of flowers allocated to everyone is different, the person who gets the most flowers will get at least () flowers.
10, three workers' masters Zhang Qiang, AARON Li and Chong Wang respectively processed 200 parts. They started to work at the same time. When the task of processing 200 parts in AARON Li was completed, Zhangjiang had processed 160, and there were still 48 parts unprocessed in Chong Wang. When Zhang Qiang finished the task of processing 200 parts, there were still _ _ parts unprocessed in Chong Wang.
1 1, there is a watch 10: 00 on October 29th, which is 4 minutes and a half slower than the standard time,165438+17: 00 on October 5th, which is 3 minutes faster than the standard time, so this watch points to1.
12. The water in the water tank flows out of the water tank at a constant speed. It is observed that at 9: 00 am, the water in the water tank is 2/3 full, and when 1 1, the water in the water tank is only 1/6. So when will the water in the tank just run out? ( )
13, Tsinghua High School * * has 1800 students. If each student has eight classes a day and each teacher has four classes a day, then there are 45 students in each class, 1 teacher. So, please tell us about the name of the teacher in the middle school attached to Tsinghua University.
Forty-five students from a class took part in the math contest. Results 35 students answered the first question correctly, 27 students answered the second question correctly, 4/kloc-0 students answered the third question correctly, and 38 students answered the fourth question correctly. So there are at least four students in this class?
15, a number first adds 3, then divides it by 3, then subtracts 5, then multiplies it by 4, and the result is 56. This number is _ _ _ _ _.
16. A bottle with a lid contains some water (as shown below). Please calculate the volume of the bottle _ _ _ _ _ _ _ _ _ cm according to the data shown in the figure. .
In a class of Grade 6 17, some students are 13 years old, some students are 12 years old, and the rest are1/kloc-0 years old. The average age of the students in this class is _ _ _ _ _ _.
18, put 25 grams of sugar into an empty cup, pour 100 grams of boiling water, fully stir, and drink half of the sugar water. Add 36 grams of boiling water. If the sugar water in the cup is as sweet as before, you need to add _ _ _ _ _ grams of sugar.
19 grade 1 class all the students participated in the extracurricular sports group and the singing group respectively, and some students also participated in both groups. If the number of people who participate in the two groups is the number of people who participate in the sports group and the number of people who participate in the singing group, then the ratio of the number of people who only participate in the sports group to the number of people who participate in the singing group in this class is _ _ _ _ _ _ _.
20. His baby panda is 2 years old this year. A few years later, when the panda was the same age as its mother, her mother was 18 years old. Mother panda is _ _ _ _ _ years old this year.
2 1, the orchard buys a batch of apples, which are divided into three grades according to quality, the best apples are first class, and the price per kilogram is 3.6 yuan; Next is your apple. The price per kilogram is 2.8 yuan; Third-class apples are 2. 1 yuan per kilogram. The ratio of these three apples is 2: 3: 1. If these three kinds of apples are sold together, it is more appropriate to price them at _ _ _ _ _ _ _ yuan per kilogram.
22, a class of no more than 60 students, in a math exam, the number of people who scored not less than 90 points, 80-89 points, 70-79 points, then there are _ _ _ people below 70 points.
23. There is a column number, which is arranged according to the following rules: 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 6, 7, ... No.2000 in this column.
24. After tripling a five-digit number with 200,000, the result is exactly the same as the number with 2 at the right end of the five-digit number. This five-digit number is _ _ _ _ _ _ _.
25. From the five natural numbers 3, 13, 17, 29, 3 1, take two numbers at a time to make the numerator and denominator of a fraction respectively, and a * * * can form _ _ the simplest fraction.
26. Due to the continuous improvement of the quality of students in Beijing 10 1 Middle School in recent years, especially the joint efforts of teachers and students, the results of college entrance examination have been improved year by year. 200 1 college entrance examination, 59% of the candidates were admitted to key universities; In the 2002 college entrance examination, 68% of the candidates were admitted to key universities; It is estimated that 74% of the candidates will be admitted to key universities in 2003. 10 1 3 The average annual growth rate of entering key universities in these three years is _ _ _ _ _ _ _ _.
27. Draw a straight line on the right through the point P in the parallelogram ABCD, and divide the parallelogram into two parts with equal area (draw a picture and explain the method).
28. 134 A school student went to the park to rent a boat. Rent a big ship, 60 yuan can take six people. Rent a boat, and 45 yuan can accommodate four people. Please design a lease scheme to minimize the rent.
29. A train passes a 900-meter-long railway bridge. It took 1 min 25 seconds to get on the bridge from the front to the back. Then the train passes through a tunnel with a length of 1 0,800 meters. It took 2 minutes and 40 seconds to get the speed of the train and the length of the car body.
30. There is a six-digit number, which is two, three, four, five, six or six digits. Their numbers are exactly the same as the original six digits, but the order is different. Find this six-digit number.
3 1, 50 pieces in a circle, number 1, 2, 3, 4, ... 50, take out every other piece, and ask that the number of the last piece left is 42, so which piece should we start with?
32. Calculate (1.6-1.125+8 (3/4)) ÷ 37 (1/6)+52.3× (3/41).
33.1February 1999, the balance of savings deposits of urban and rural residents nationwide at the end of the month was 5,676.7 billion yuan, and the balance was 1000 billion yuan; 127; Compared with the balance at the beginning of the month, it increased by 18%, so the balance of savings deposits of urban and rural residents nationwide at the beginning of February was () billion yuan (accurate to 100 million yuan).
34. The circumference of the circular runway is 400 meters. Two athletes, A and B, set off clockwise from the starting point at the same time. The speed of A is 400 meters per minute, and the speed of B is 375 meters per minute. () Minutes later, Party A and Party B meet again.
35. The least common multiple of two integers is 1925. These two integers are divided by their greatest common divisor, and the sum of the two quotients is 16. These two integers are () and () respectively.
36. In the math exam, one question is to calculate the average of four scores (5/3), (3/2), (13/8) and (8/5). Xiaoming was careless and copied the numerator and denominator of 1 fraction upside down. The biggest difference between the wrong average and the correct answer is ().
37. The fruit company bought 52,000 kilograms of apples, with the purchase price of 0.98 yuan per kilogram, and paid the freight and other expenses 1.84 yuan, and the estimated loss 1%. If you want to make a profit after all buying and selling 17%. The retail price of apples per kilogram should be set at () yuan.
38. Calculation:19+199+1999+...+19999 ... 99
└ 1999 9┘
39. Xinxin Business Service Company charges 3% service fee for customers to sell goods and 2% service fee for customers to shop. Today, a customer entrusted the company to sell some self-produced goods and buy new equipment. It is known that the company * * * deducted the customer service fee of 264 yuan, and the customer just broke even. How much did the new equipment cost?
40, a column number, the first three are 1, 9, and each after 9 is the remainder obtained by dividing the sum of the first three adjacent numbers by 3. What is the number 1999 in this column number?
4 1, a cuboid wood with a volume of 0.078 cubic meters. It is known that this wood is 1.3m long and 3m wide. How many decimetres should it be? Sun Jian politicians calculated the height error to be 3 meters. In this way, what is the volume of this piece of wood of more than 0.078 cubic meters?
42. There are two squares, one big and one small. They are 20 cm apart in circumference and 55 cm apart in area. How many square centimeters is the area of a small square?
43. There are nine small rectangles whose length and width are equal respectively. The area of the big rectangle composed of these nine small rectangles is 45 square centimeters. Find the circumference of this big rectangle.
44、 77× 13+255×999+5 10
45. A = 8.8+8.98+8.998+8.9998+8.99998, and the integer part of A is _ _ _ _.
46. The divisor of 1995 * * is _ _ _.
47. The equation "Melissa Zhou × Hao Hao+Math = 1994" means the product of two numbers. When one number is added, the total is 1994. In the formula, the three Chinese characters "Xue, Hao and Shu" each represent three different numbers, among which "Shu" stands for _ _ _ _.
48. As shown in the figure 1, the seven Chinese characters "Hao, Gang, Companion, Help, Hand, Shen and Qiu" represent the seven numbers 1 ~ 7. It is known that the five sums obtained by adding three numbers on three straight lines and three numbers on two circles are all equal. The "good" in the middle of the picture stands for _ _ _.
49. Uncle Agan, a farmer, wants to build a rectangular chicken coop with * walls with 20 pieces of metal nets 2 meters long 1.2 meters wide (as shown in Figure 2). In order to prevent chickens from flying out, the height of the henhouse should not be less than 2 meters. In order to maximize the area of henhouse, the length of BC should be 100 meter.
50. Xiao Hu and Xiao Tu calculate the product of two digits of A and B. Xiao Hu misread the single digit of A, and the calculation result is1274; Xiao Tu misread the ten digits of a number, and the calculation result was 8 19. One number is _ _ _ _.
In the 5 1 and 1994 World Cup, four teams, A, B, C and D, were in the same group. In the group stage, each of the four teams will play a game with the other three teams. According to the regulations: the winning team in each game can get 3 points; The losing team gets 0 points; If the two sides draw, each team will get 1 point. Known:
(1) The total scores of the four teams in three games are divided into four consecutive odd numbers;
(2) Team B ranked first in total score;
(3) Team D only tied with the other team twice, one of which was tied with Team C. ..
According to the above conditions, it can be inferred that the total score of team _ _ _ ranks fourth.
52. There are 2 16 bricks stacked on an open space (as shown in Figure 3). This pile of bricks has two walls. Now cover the surface of this brick pile with lime, and there are _ _ _ _ _ blocks of lime-coated bricks.
53. In an enterprise in a southern city, 90% employees are shareholders, 80% employees are "10,000 yuan households" and 60% employees are wage earners. Then, at least _ _% of the "ten thousand households" in this enterprise are shareholders; At least _ _ _ _ _ _ (fill in a score) of the wage earners are "ten thousand households".
54. There is a bug on the grid paper (Figure 4), which starts from a point O on the straight line AB and crawls along the horizontal or vertical line on the grid paper. The length of each paragraph on a square paper is 1 cm. After climbing a few short sections, the bug is still on the straight line AB, but it does not necessarily return to the O point. If a bug crawls more than 2 cm, there are _ _ _ kinds of crawling routes; If the bug crawls more than 3 cm, the crawling route of the bug is _ _ _ _.
55. Natural numbers are arranged according to certain rules as follows:
According to the arrangement law, 99 ranks in the _ _ _ row and the _ _ _ column.
56. As shown in Figure 5, AF=2FB, FD=2EF, and the area of right triangle ABC is 36 square centimeters. Find the area of parallelogram EBCD.
57. Limin Store bought a batch of mosquito-repellent incense from a grocery company, and then sold it at a price increase of 40% per bag according to the net profit it hoped to make. However, when 90% of the mosquito-repellent incense was sold at this price, the summer passed quickly. In order to speed up the capital turnover, the store sold all the remaining mosquito-repellent incense at a preferential price of 30% off the price. So the actual net profit is less than the expected net profit 15%. According to the regulations, no matter what the price, after selling this batch of mosquito-repellent incense, business tax 300 yuan should be paid (taxes and money used to buy mosquito-repellent incense as the cost). How much did it cost to buy this batch of mosquito-repellent incense at Limin Store?
58. Three oil drums, A, B and C, each contain several kilograms of oil. For the first time, part of the oil in barrel A was poured into barrel B and barrel C, so that the oil in barrel B and barrel C was doubled respectively. Pour the oil in barrel B into barrel C and barrel A for the second time, so that the oil in barrel C and barrel A is twice as much as that before the second pouring; Pour the oil in barrel C into barrel A and barrel B for the third time, so that the oil in barrel A and barrel B is twice as much as that in the previous barrel for the third time, so that the oil per barrel is 16kg. How many kilograms of oil were originally contained in the three oil drums A, B and C?
59. Gardeners should plant trees equidistantly at the edge of a circular flower bed with a circumference of 300 meters. They first dug a hole every 3 meters along the edge of the flower bed. When they finished digging 30 holes, they were suddenly told that they would plant a tree every 5 meters instead. In this way, how many holes will they have to dig to complete the task?
60. A college student who learns from Lei Feng's group works in a restaurant for half an hour every day, and everyone can earn 3 yuan money. By165438+1October 1 1, they had earned 1764 yuan. The team plans to earn 3000 yuan before February 9, 2008 and donate it to Project Hope. So the team must add one person in a few days. Q: This extra person has to work in the restaurant every day from the date of 165438+ 10, so that he can earn exactly 3000 yuan before the date of 65438+February 9?
6 1, there are male and female athletes practicing long-distance running on the circular track, the running speed is constant, and the male athletes run a little faster than the female athletes. If they start from the same starting point and run in the opposite direction at the same time, they will meet every 25 seconds. Now, they start from the same starting point and run in the same direction at the same time. 13 minutes later, the male athlete caught up with the female athlete. How many laps did the female athlete run when she caught up? (The number of laps is rounded off)
Is the sum of all digits in the multiple of 62.555555 odd? If yes, please give examples; If not, please explain why.
63. The picture on the right is a right-angled trapezoid. Please draw a line segment and divide it into two quadrangles with the same shape and equal area. (Please indicate the data and symbols indicating the position of the line segment or write a diagram).
64. The following five figures have two characteristics: (1) consists of four squares of the same size connected together; (2) Every small square has at least one common edge with another small square. We call the graph with the above two characteristics "Tetris".
If a Tetris rotates on a plane, which is the same as another Tetris (such as B and E in the above picture), then these two Tetris are only one kind.
In addition to the above four kinds, there are several Tetris. Please draw them all.
65. Fill in the appropriate operation symbols in the following "□" to make the equation hold: (1□ 9 □ 2) × (1□ 9 □ 2) × (19 □ 9 □ 2) =1992.
66. The length of an isosceles trapezoid with three sides is 55cm, 25cm and 15cm respectively, and its base is the longest side. Therefore, the circumference of this isosceles trapezoid is _ _ cm.
There are 90 seats on a row of benches, and some seats have been taken. At this moment, another man came and sat on this bench. Interestingly, no matter where he sits, he is adjacent to the person who has already sat. It turns out that at least _ _ people have been seated.
68. 1992 divided by the natural number a, the quotient is 46, the remainder is r, a=__, and r=__.
69. On the Double Ninth Festival, 25 old people came to Yanling Teahouse for tea. Their ages are exactly 25 consecutive natural numbers. Two years later, the sum of the ages of these 25 old people is exactly 2000. The oldest of them is _ _ _ years old this year.
70. The school bought several books on history, literature and art, and popular science, and each student borrowed two at will. Then, at least two of these _ _ _ students must have borrowed similar books.
7 1, a math contest, five players got 404 points, and their scores were not equal, and the player with the highest score got 90 points. Then the player with the least score will get at least _ _ _ _ points and at most _ _ _ _ points. (Each player's score is an integer)
72. It is necessary to saw the high-quality copper tube with a length of 1 meter into a small copper tube with a length of 38 mm and 90 mm, and it will consume 1 mm copper tube every time. Then, only when the sawed 38 mm copper tube is _ _ _ _ _ section and the sawed 90 mm copper tube is _ _ _ _ _ _ section, the copper tube loss can be minimized.
73. Two construction teams, Party A and Party B, are building a 4200m-long highway, and Team B is building 100m more than Team A every day. Now it will be repaired by engineering team A for 3 days. The rest of the road sections were jointly repaired by Team A and Team B, and it took only 6 days to complete. Q: How many meters do the A and B engineering teams build roads every day?
74. A person rides a bicycle from the county seat to the township to set up a factory. He started from the county seat by bike and completed half the journey in 30 minutes. At this time, he sped up, driving 50 meters more every minute than before. After riding for another 20 minutes, he knew from the mileage card on the roadside that he had to ride another 2 kilometers to set up a factory in the township, and asked for the total distance from the county to the township.
75. The width and height of a cuboid are equal, both equal to half the length (as shown in figure 12). Cut this cuboid into 12 small cuboids, and the sum of the surface areas of these small cuboids is 600 square decimeters. Find the volume of this big cuboid.
There are 1992 buttons. Two people take turns to take a few buttons from them, but each person takes at least 1 buttons and at most 4 buttons. Whoever takes the last button loses. Q: What are the countermeasures to ensure victory?
77. There is a square piece of thick paper with a side length of 24 cm. If you cut a small square at each of its four corners, you can make a carton without a lid. Now, to maximize the size of the carton, how many centimeters should the side length of the cut cubes be?
78. Jin Shifu, an individual blacksmith shop, needs two shapes of iron blanks (A) and (B) as shown in Figure 13 to process some iron products. At present, there are two pieces of scrap iron A and B (as shown in figure 14 and figure 15). The small squares in figure 13, figure 14 and figure 15 are all equilateral squares. Jin Shifu wants to choose one piece from them, so the selected iron sheet is just suitable for processing the complete set of this iron sheet product ("complete set" means that there are as many iron sheets as (a) and (b)) without wasting any materials. Q: (1) Which scrap iron should Jin Shifu choose from? (2) How to cut the selected scraps? Please draw a cut line mark on the picture or use a shadow to indicate the blank space of a shape. )
79. Just modify one digit of 2 1475, and the modified number can be divisible by 225. How to modify it?
80.( 1) How to divide nine identical chocolates equally among four children (each chocolate can only be cut into two pieces at most)?
(2) If the word "four" in the above (1) is changed to "seven", will it be divided? If so, how to do it? If not, why?
Preliminary examination questions of the 4 th China Jinbei Youth Mathematics Invitational Tournament
Preliminary examination questions of the 4 th China Jinbei Youth Mathematics Invitational Tournament
1. Please write the calculation result of the following formula as a fraction:
2. There are 13 nails on a board (right). A few nails can be covered with rubber bands to form triangles, squares, trapezoids and so on (below). Please answer: How many squares can be formed?
3. Here is a cylinder and a cone (below). Their height and base diameter are marked on the map, and the unit is cm. Please answer: What is the ratio of cone volume to cylinder volume?
There are five scores here:,,,,. In descending order, which number is in the middle?
Nowadays, the popular variable-speed bicycle is equipped with several gears with different numbers of teeth on the drive shaft and the rear shaft respectively. Different gears are connected by chains, and several different speeds are obtained through different transmission ratios. There are three gears on the transmission shaft of "Hope" variable-speed bicycle, with the number of teeth being 48, 36 and 24 respectively. There are four gears on the rear axle, with the number of teeth being 36, 24, 16 and 12 respectively. Q: How many different speeds does this gearbox have?
6. The ABCD area of a large square in the figure is 1, and other points are the midpoint of its sides. Excuse me: What is the area of the shadow triangle? (see the picture below)
7. In the formula on the right, the sum of the addends is three times that of the sum. Q: What is the addend at least?
8. There are 60 apples in the basket. Take them all out and divide them into even piles so that the number of each pile is the same. Q: How many ways are there?
9. Xiaoming plays the game of rings, and he gets 9 points for a chicken, 5 points for a monkey and 2 points for a puppy. Xiao Ming * * * sets 10 times, and each small toy is trapped at least once. Xiao Ming 10 times 6 1. Q: How many times has the chicken been caught?
10. Many two-wheeled motorcycles and four-wheeled sleeping cars are parked in the garage, and the ratio of the number of cars to the number of wheels is 2: 5. Q: What is the ratio of the number of motorcycles to the number of sleeping cars?
1 1. There is a clock, which is 25 seconds slow every hour. At noon on March 2 1 Sunday 12 this year, the instructions were correct. Excuse me, when will this clock show the correct time next time?
12. Someone goes from place A to place B. If he rides a motorcycle from the first place 12 hours and then rides a bike for 9 hours, he just arrives at the second place. If he rides a bike from A for 2 1 hour, and then rides a motorcycle for 8 hours, and just arrives at B. Q: How many hours does it take to ride a motorcycle to B?
13. The two circles in the picture below have only one thing in common: A, the big circle is 48 cm in diameter and the small circle is 30 cm in diameter. Two beetles started from point A at the same time and crawled along two circles at the same speed in the direction indicated by the arrow. Q: How many times did the beetle climb on the small circle? Are the two beetles the farthest apart?
14. If you sell a juvenile book at the original price, you will make a profit of 0.24 yuan for each book sold; Now the price has been reduced, as a result, the book sales have doubled and the profit has increased by 0.5 times. Q: How much is the price reduction for each book?
15 There is a four-story building. The four glasses of each window are painted red and white respectively, and each window represents a number (below).
There are three windows on each floor, representing a three-digit number from left to right. The three digits represented by four floors are: 79 1, 275, 362, 6 12. Q: What are the three numbers on the second floor?
Examination questions of the 4th Huajin Cup Junior Mathematics Invitational Tournament.
1. Simplify
The TV station will broadcast a 30-episode TV series. If the number of episodes scheduled to be broadcast every day is not equal to each other, how many days can the TV series be broadcast at most?
Just a cylinder with a volume of 628 cubic centimeters can be put into a square carton. What is the volume of this carton? (Pi =3. 14)
There is a basket of apples. After dividing them into three equal parts, there are still two apples left. Take out two, divide them into three parts, and there are two left; Then take out two, divide them into three parts, and there are two left. Q: How many apples are there in this basket?
calculate
6. The circumference of the rectangular ABCD is16m. Draw a square on each side of it. It is known that the sum of the areas of these four squares is 68 square meters. Find the area of rectangular ABCD.