![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
The perimeter of the circular track is 500 meters. A and B start from the starting point in a clockwise direction at the same time. A runs 120 meters per minute, B runs 100 meters per minute. Both of them stop every 200 meters to rest for one minute. How many minutes does it take for a to catch up with B for the first time?
Because when a runs 200 meters, the time to start is 200 ／ 120 + 1 ＞ 2 minutes. So at this time, when B runs for 2 minutes, the place where B runs is 100 × 2 = 200 (meters), which means that B runs for 2 minutes and stops at the place 200 meters away from the resting a
Mr. Zhang has 3 shirts, 4 pairs of trousers and 2 pairs of shoes. They can be used in () different ways
A. 9B. 14C. 24D. 6
3 × 4 × 2 = 24 (species), a: they can be used to match 24 different wearing methods
The greatest common divisor and the least common multiple
1) There is a natural number, which is divided by 6 to 1, divided by 5 to 1, and divided by 4 to 1. What is the minimum natural number?
2) How many pieces can we cut the iron plate 120 cm long and 80 cm wide into the largest square with equal area and no surplus?
3) How many cubes can be sawed from the wood 132 cm in length, 60 cm in width and 36 cm in thickness?
4) A box of pens can be divided equally among 2, 3, 4, 5 and 6 students. How many pens does this box have?
5) Use 96 red flowers and 72 white flowers to make a bouquet. If the number of red flowers in each bouquet is the same, so is the number of white flowers. How many flowers are there at least in each bouquet?
6) From Xiaoming's home to the school, there used to be 55 poles installed every 50 meters, plus two poles at both ends. Now there is one pole installed every 60 meters. Apart from the two poles at both ends, how many poles do not need to be moved in the middle?
7) On a stick with a length of 100 cm, dye a red dot every 6 cm from left to right, and dye a red dot every 5 cm from right to left. After dyeing, cut the stick section by section along the red dot. How many short sticks are there with a length of 1 cm?
8) How many pears are there at least in each basket if there are one more pear for each two pears, two more pears for each three pears and four pears for each five pears?
9) Now there are 42 kg bananas, 112 kg apples and 70 kg oranges, which are distributed to several classes in the kindergarten on average. The number of these three kinds of fruits allocated to each class is equal. How many classes are allocated at most? How many kg of each of the three kinds of fruits are allocated to each class at least?
10) There are three iron wires, one 54 meters long, one 72 meters long and one 36 meters long. They should be cut into small sections of the same length, and no surplus is allowed. What is the maximum length of each section?
The greatest common divisor and the least common multiple
1) Every five years, they went boating. They calculated how many people there would be in this class if one boat was added and six people would sit in each boat. If one boat was reduced and nine people would sit in each boat?
2) There is an electronic watch. Every 9 minutes, the light will ring once on the hour. At 12 o'clock at noon, the electronic watch will ring and light up. When is the next time?
3) The least common multiple of two integers is 140, the greatest common divisor is 4, and decimals cannot divide large numbers
4) What is the minimum number of a number that is divided by 2 to 1, by 3 to 2, by 4 to 3, by 5 to 4, by 6 to 5?
5) Three kinds of drinks are provided at a dinner. According to the statistics after dinner, there are 65 bottles of the three kinds of drinks. On average, every two people drink a bottle of drink a, every three people drink a bottle of drink B, and every four people drink a bottle of drink C. how many people participate in the dinner?
6) Given that the greatest common divisor of a and B is 6, the least common multiple is 84, and a × B = 42, find B
7) The greatest common divisor of two numbers is 12, the least common multiple is 180, and the larger number cannot be divided by the smaller number,
8) The greatest common divisor of a and B is 75 and the least common multiple is 450
9) Given that the greatest common divisor of a and B is 31, and a × B = 5766, find a and B
10) There is a plate of fruit, 3 more than 2, 4 more than 3, 5 more than 4. How many fruits are there in this plate?
The greatest common divisor and the least common multiple
1、61
2、6
3、165
4、60
5、7
6、8
7、13
8、29
9. 14 classes of banana, apple, orange three kinds of fruit were divided into 3, 8, 5 kg
10、18
The greatest common divisor and the least common multiple
1、36
2. 3 p.m
3. 20 and 28
4、59
5、60
6. Wrong title: in the title, a × B = 42 and the least common multiple of a and B is 84
7. 36 and 60
8. 150 and 225
9. 62 and 93 or 31 and 186
10、59
I did it in a hurry. If you have any objection, please ask
Qingyuan County song and dance troupe's original number of male actors is four times that of female actresses. Due to the recent transfer of an actress, the number of male actors is now five-quarters of that of female actresses. How many actors are there in the troupe now?
Suppose there were x actresses
4/3X=5/4(X+1)
4/3X=5/4X+5/4
X=15
So now the number of actors in the group is: 15 + 15 × 4 / 3 + 1 = 36
A: now there are 36 actors in the group
You can check my answer. I promise it's absolutely right
Uncle Chen rides a bicycle from place a to place B, traveling 10 kilometers per hour, arriving at 1:00 p.m. and 15 kilometers per hour, arriving at 11:00 a.m. he wants to arrive at 12:00 p.m., how many kilometers per hour should he travel?
There is a difference of two hours between the arrival at 1:00 p.m. and that at 11:00 a.m. because there are more than 15-10 kilometers per hour, it is only two hours ahead of schedule
So he traveled 15 kilometers per hour, 10 * 2 / 5 = 4 hours, so his departure time was 11-4 = 7 am
The distance between land a and land B is 15 * 4 = 60 km
12-7 = 5 hours
So he wants to arrive at 12 noon, and he should travel 60 / 5 = 12 kilometers per hour
There is a cube wood block with an edge length of 1 meter. If you saw it into 8 small cubes of equal volume, how many square meters will the surface area increase?
1 △ 2 = 0.5 (m), 0.5 × 0.5 × 6 × 8 = 12 (M2), 1 × 1 × 6 = 6 (M2), 12-6 = 6 (M2); answer: the surface area increases by 6 m2
A, B, C, D four students sports shirt printed with different numbers: Zhao said: "a is No. 2, B is No. 3." Qian said: "C is No. 4, B is No. 2." Sun said: "D is No. 2, C is No. 3." Li said: "D is No. 1, B is No. 3." also know that Zhao, Qian, sun, Li each said only half right. Excuse me: C's number?
Suppose that the first half of Zhao's sentence "a is No. 2" is right, then Qian said: "C is No. 4, B is No. 2", "C is No. 4" is right, because B can no longer be No. 2; Sun said "Ding is No. 2, C is No. 3" is not right, which is in contradiction with the requirements of the topic, so this assumption is not tenable
Primary school Olympiad Mathematics drawing inferences from one instance
Basic volume
1.40 * 50 / 10 = 20 (days) (40 + 10) * 20 = 1000 (pieces)
2.240 / [(240-48) / 24] = 30 (sets)
3.1.8-1.8*30/（30+6)=0.3(t)
4. (30-10) / (30-25) = 4 (sheets) 4 * 25-10 = 90 (sheets)
51 / (80 / 4 / 5 + 36 / 8) = 6 times
6.18-15 * 4 * 18 / (15 + 3) / (4 + 1) = 6 days
Improve the volume
1. (100-2) / (6 + 8) = 42 Cunninghamia lanceolata trees
100-42 = 58 poplar trees
2.100 * (20 / 2) / (20-5-20 / 2) = 200
200 * (20-54) = 3000
3000 * 2 = 6000
3.（3000-500）/（3000-1000）=1.25
1000-500 / 1.25 = 600m
4.60 / 3 = 20 seconds 20-10 / 5 = 18 seconds
18 * 100 / 20 = 90 lanes
5. (600 + 120 + 120) / 2 = 420
[420 * (3-2) + 120] / 3 = 180 copies a
6.108 + 7 * 10-2 * (27 + 7) = 110 yuan
110 / (10 + 5-2 * 2) = 10 sheets ···· five yuan
10-7 = 3 pieces of ten yuan
27-10-3 = 14 pieces
Version b week 35
465850x465850-465849x456851
Let 465850 be a
Then a × a - (A-1) × (a + 1)
=a×a-（a×a+a-a-1）
=a×a-a×a+1
=1
Primary School Mathematical Olympiad give a negative, third and fifth grade B average 1 basic and improve all the answers
Basis: 1. (91 * 2 + 88 * 2 + 93 * 2) / 2 = 272 (points) The sum of the number of words is 272-91 * 2 = 90 (points) English 272-88 * 2 = 96 (points) Mathematics 272-93 * 2 = 86 (points) 2. (10.3-9.13) * 35 = 40.95 (yuan) 40.95 / (9.13-8.5) = 65 (kg) 3. (148-14
RELATED INFORMATIONS
- 1. Three questions of crazy 2 on three pages
- 2. A cuboid becomes a cube when its height increases by 4cm. At this time, its surface area increases by 112cm. What is the surface area of the cuboid?
- 3. 1. There are 180 red, white and black beads of the same size, arranged in five red, four white and three black. Q: what color is the 158th one? How many black beads are there? 2. There is a row of colored lights on the roadside. There are red, yellow and green lights between the two white lights. Then, what color is the 80th light?
- 4. 1. When the student asked the teacher how old he was, the teacher said, "when I was your age, you were just 3 years old; when you were my age, I was 39 years old." so how old is the teacher? 2. Yaya, Benben and LeLe have 73 pieces of sugar. If Yaya eats 3 pieces, Benben and Yaya have the same amount of sugar. If Benben gives Lele 2 pieces of sugar, Lele's sugar is twice as much as Benben's. how many pieces of sugar do they have? 3. There are two pieces of land with a total area of 80 hectares. Three times of the first piece of land is 10 hectares less than two times of the second piece of land. How many hectares are there in each of the two pieces of land? 4. This year, my grandfather's age is six times that of xiaolingmei. A few years later, my grandfather's age is five times that of xiaolingmei. A few years later, my grandfather's age is four times that of xiaolingmei. Q: how old is my grandfather?
- 5. The distance between a and B is 24 km. The fast and slow trains are both from a to B. when the fast train leaves, the slow train has already run for 4 km. When the fast train arrives at B, the slow train is 2 km away from B. how far is the fast train from B to catch up with the slow train? When the fast train runs 24 km, the slow train actually runs 24-4-2 = 18 (km), that is, the fast train runs 6 (km) more than the slow train. After that, I don't know how to do it,
- 6. A and C start from a and B in the same direction at the same time. 24 minutes after a passes B, a catches up with B. at this time, C just walks to B, and B returns immediately. A and C keep the same direction and continue to walk. When B and C meet, a returns immediately. B and C keep the same direction and continue to walk. After another 36 minutes, a and C meet at 3 kilometers away from B, then B has already walked to a__ Km away
- 7. A passenger car and a freight car leave from ab at the same time and run in opposite directions. The distance between AB and ab is 825km. Five hours after the two cars meet, the passenger car arrives at B. seven and two hours after the two cars meet, the freight car arrives at a. how many kilometers does the passenger car travel per hour?
- 8. A, B and C are three stations on the same road. The distance from station B to station a and C is equal. Xiaoqiang and Xiaoming start from station a and C at the same time and face each other. Xiaoqiang meets Xiaoming 100 meters after station B, and then they go on. Xiaoqiang returns to station C, and overtakes Xiaoming 300 meters after station B. question: what's the distance between station a and station B? Do you know how to solve this problem
- 9. In the 13th century, Italian mathematician Leonard raised the following interesting question: if each pair of big rabbits gives birth to a pair of little rabbits every month, and each pair of little rabbits becomes big rabbits after growing for a month, and all rabbits survive, how many pairs of little rabbits will there be after a year when someone raises a pair of newborn rabbits? It's better to have a formula. Why do you do it like this?
- 10. Xiaomei is 8 years old and her father is 36 years old. When Xiaomei was how old, her father was three times as old as Xiaomei Equations to be listed
- 11. What does △ mean in Olympiad Mathematics?
- 12. Sentence making: Feather like reed wadding Wolf eyes For... For... For can 't help laughing: have quick wits idea occurred to one 's mind at the crucial moment: Questions on famous sayings and sentences Frustration: Inspiration: success: What's the price of the coat and trousers? The price of trousers is one third of that of the coat, and a suit costs 320 yuan In the first quarter, a 12 km highway was built, and in the second quarter, a 35 km highway was built. In the second quarter, 1 / 45 of the total length of the highway was built more than in the first quarter? The total yield of grapes in a vineyard last year was 20000 kg, which is one fourth higher than that of last year. What is the total yield of this vineyard this year? Note: to solve the equation, there must be a set
- 13. 1.（+14）+（-4）-（-2）+2 2. (- 8) * (- 2) △ 4 * (- quarter) 3. - 2 & # 178; △ 4 / 9 * (- 2 / 3) &# 178; 4. - 1 & # 178; &# 186; &# 185; &# 185; - (1 + 0.5) * one third ／ - 4
- 14. There are four squares (as shown in the figure below) with side lengths of 1m, 2m, 3M and 4m respectively. How much of the area of the white part is that of the shadow part?
- 15. Let n be a positive integer and prove that the number 2 Λ 2 Λ n + 2 Λ 2 Λ (n-1) + 1 has at least n different prime factors The formula is to the power of 2 (n power of 2), plus the power of 2 (n-1 power of 2), plus 1
- 16. A factory a and B two workshops, last year plans to complete the tax and profit of 7.5 million yuan, the result of a workshop 15% over the plan, B workshop 10% over the plan, the two workshops jointly complete the tax and profit of 8.45 million yuan, ask these two workshops last year to complete the tax and profit of how many million yuan?
- 17. A store made a profit of 15000 yuan in January, 6000 yuan more in February than in January, 4000 yuan less in March, 2000 yuan more in April than in March, and 13000 yuan more in May. Try to calculate the profit and loss of the store in the first five months
- 18. ①ab^2- ab(b-a)+(-2a)^2 ·x ②1/3 x(-x^2 +2x-1 )-1/3x^2(2x-6x^2)
- 19. There are two kinds of sulfuric acid solutions with different mass fractions. The mass fraction of type A is 90% and that of type B is 75%. Now we need to prepare 12 kg of 85% sulfuric acid solution. How many kg of each of the two sulfuric acid solutions?
- 20. 3x + 4 / (X-2) (x + 1) = A / (X-2) - B / (x + 1), where a and B are constants 4A-B／4A+B