2. Young Pioneers will participate in tree planting activities, and each will plant 2 trees. If one person digs a hole, one person needs 25 points, a trip to transport seedlings (up to 4 trees) needs 20 points, a bucket of water (which can water 4 trees) needs 10 points, and a tree needs 10 points. Now, in pairs, it will take at least minutes to complete the task of planting trees.
3.1992×1992×1992× …×1992 (* * *1992), what is the tenth place of the product?
There are 192 books on the third shelf. Now, take out as many books from the upper level and put them in the middle level, and then take out as many books from the middle level and put them in the lower level. Finally, take out as many books as the upper layer from the lower layer and put them on the upper layer. At this time, the books on the three shelves are just equal. So, there are books on the upper, middle and lower floors respectively.
5. Four classes in Grade Five held a math contest. Xiao Ming guessed that the result of the contest was
1. Five cards are written with numbers: 0, 0, 1, 2, 3, which can be used to form many different five-digit numbers. Find the average of these five numbers.
2. The rabbit and the kitten go upstairs together. A kitten is twice as fast as a rabbit. When the rabbit went up to the fourth floor, the kitten went up to the () floor.
3. A kind of weed, which grows 1 time every day, can grow to 48mm in 12 days, and it takes () days to grow to 6 mm..
Xiao Qiang has two packages of sweets, one with 48 capsules and the other with 12 capsules. He took three capsules out of the extra package at a time and put them into fewer packages. After () times, the number of two packs of candy can be equal.
5. Write a string of numbers immediately after 4444, and each number written is a digit of the product of its previous two numbers. For example: 4×4= 16, write 6,4× 6 = 24 after 4, and write 4 after 6 to get a series of numbers: 4444644644 ... This series of numbers starts from 1 and counts to the right. The 444th digit is ().
6. Mom is frying eggs in the pot. Eggs should be fried on both sides. Fry each side for 30 seconds. This pot can only fry two eggs at the same time. It takes at least () seconds to fry three eggs now.
7. There are two piles of fruit, a pile of apples and a pile of pears. If 1 apple is replaced by 1 pear, there are two more apples. If 1 pear is replaced by two apples, there are 1 pear. Think about it, there are () apples and () pears.
8. A road has been built, with 2.6 kilometers left. It is known that there are 0.2 kilometers more unrepaired than repaired. The total length of this road is () kilometers.
9. A barrel of oil weighs 5.6 kg, and the barrel weighs 3. 1 g after half of the oil is used. The net weight of this barrel of oil is () kilograms.
10. pesticide plant produces a batch of pesticides with a daily output of 0.24 tons. If the price is 28.5 yuan per 500 grams. The value of pesticides produced by this factory every day is () yuan.
1 1. Knowing that the numbers A, B, C and D are not zero, we know that:
Number A ÷ B =0.5 number D ÷ B = 1.0 1 number c ÷ 0.4 = b.
A number ÷ 1.25= C number
Compare the sizes of four numbers, A, B, C and D, in descending order, and the third number is ().
12.3.704 The number after the decimal point of 100 is ().
13. 1993× 199.2- 1992× 199. 1=( )
14. 15.37×7.88-9.37×7.88- 15.37×2. 12+9.37×2. 12=( )
15. There are three people, A, B, C, A walks 50 meters per minute, B walks 40 meters per minute, and C walks 60 meters per minute. A, B set out from East Village, C set out from West Village, and set out at the same time. A meets C 40 minutes after takeoff, and B meets C 40 minutes after takeoff.
There was a general named Han Xin in the Han Dynasty in China. Every time he counts soldiers, he only asks his men to count off at L ~ 3, 1 ~ 5, 1 ~ 7, and then reports the remainder of each team's count, so he knows how many people have arrived. His ingenious algorithm is called "Ghost Valley Calculation", "Partition Calculation" or "Han Xin's Point Force", and foreigners call it "Chinese remainder theorem". Cheng Dawei, a mathematician in the Ming Dynasty, summed up this algorithm in his poem. He wrote:
Three people walk seventy, five trees and twenty-one sticks,
Seven sons reunited in the middle of the month and didn't know until 105.
The meaning of this poem is: multiply the remainder obtained by dividing 3 by 70, the remainder obtained by dividing 5 by 2 1, and the remainder obtained by dividing 7 by 15. If the result is greater than 105, subtract the multiple of 105, and you will know the number you want.
For example, there must be 52 eggs in a basket. If there are 3 eggs in 3 places, 1, there are 5 eggs in 5 places, 2 eggs in 7 places and 3 eggs in 7 places. The formula is:
1×70+2×2 1+3× 15= 157
157- 105 = 52 (pieces)
Please calculate the following questions according to this algorithm.
Xinhua primary school subscribed to a batch of China Youth Daily. If there are three digits, the remainder is 1. Five plots of land, and the rest are two; Seven pieces of land, and the rest is two pieces. How many copies of China Youth Daily did xinhua primary school subscribe to?
Pucsok's interesting question.
Puccio is a famous mathematician in the former Soviet Union. 195 1 wrote a book, Math Teaching Methods in Primary Schools. There is an interesting question in this book.
This shop sold 1026 meter cloth in three days. The sales volume of the second day is twice that of the first day; On the third day, it sold three times as much as the next day. How much rice cloth do you want to sell in three days?
The problem can be thought of this way: the number of meters sold on the first day is regarded as 1 serving. You can draw the following line segment diagram:
The first day 1 serving; The second day is twice as much as the first day; The third grade is three times that of the second grade, and the first grade is 2×3 times.
Comprehensive calculation shows the number of meters of cloth sold on the first day:
1026÷(L+2+6)= 1026÷9 = 1 14(m)
And 1 14× 2 = 228 (m).
228× 3 = 684m
So the fabrics sold in three days are: 1 14m, 228m and 684m respectively.
Please do the problem in this way.
Four people donated money for disaster relief. B donated twice as much as A, C donated three times as much as B, D donated four times as much as C, and they donated 132 yuan. How much do you want each of the four people to donate?
Newton problem
Newton, a great British scientist, once wrote a math book. There is a very famous topic in the book about cattle grazing on pasture. Later, people called this kind of topic "Newton problem".
The "Newton problem" is like this: "There is a pasture where 27 cows are known to have been raised and the grass has been eaten up in 6 days; Raise 23 cows and eat all the grass in 9 days. If you have 2 1 cow, how many days can you eat all the grass on the pasture? And the grass on the pasture is growing. "
The general solution to this kind of problem is: regard the grass eaten by A Niu Yiri as 1, then there are:
(1) The forage for 27 cows for 6 days is 27× 6 = 162.
(This 162 includes original grass and 6-day new grass. )
(2) The pasture eaten by 23 cows in 9 days was 23× 9 = 207.
(This 207 includes the original grass in the pasture and the grass that has grown for 9 days. )
(3) 1 day: (207-162) ÷ (9-6) =15.
(4) The grassland is 27× 6- 15× 6 = 72.
(5) Feed new grass to 15 cows every day, subtract 2 1 cow from 15 cows, and the remaining 6 cows eat grass from the original pasture:
72 ÷ (21-15) = 72 ÷ 6 =12 (days)
Therefore, it takes 12 days to feed 2 1 cow and eat all the grass on the pasture.
Please calculate it.
There is a pasture, if you raise 25 sheep, you can eat all the grass in 8 days; Raise 2 1 sheep and eat all the grass in 12 days. If you raise 15 sheep, how many days can you eat up the grass growing on the pasture?
Responder: God of Meteor Shower-Probation Period Level 1 7-29 20:57
1. Write 789 () times in a row, and the number can be divisible by 9, which is the smallest.
2. There are six cases of goods in the store weighing 15, 16, 18, 19, 20, 3 1 kg respectively, and two customers bought five cases. It is known that the weight of goods bought by a customer is twice that of a customer. Q: What is the weight of the remaining box of goods in the shop?
2000 Primary School Mathematical Olympiad Examination Questions
Preparatory work (a)
1. Calculation:12-22+32-42+52-62+…-1002+1012 = _ _ _ _ _.
2. A two-digit number is equal to the sum of its one-digit number and the square of its ten-digit number. This two-digit number is _ _ _ _ _.
3. Five consecutive natural numbers, each of which is a composite number, and the minimum sum of these five consecutive natural numbers is _ _ _ _ _ _ _.
There are several red and white balls. If you take out a red ball and a white ball at a time, there will be 50 white balls when you can't get the red ball; If you take one at a time,
Red ball and
Three white balls, so when there are no white balls, there are 50 red balls left. Then this pile has _ _ _ _ _ _ _ red balls and white balls.
5. The age of a young man this year (2000) is exactly equal to the sum of the figures of the year of birth, so the age of this young man this year is _ _ _ _ _ _ _.
6. As shown on the right, ABCD is a parallelogram with an area of
72 square centimeters, e and f are AB and BC respectively.
Point, the area of the shaded part in the figure is _ _ _ _ flat.
Square centimeters.
7.a is a 2000-bit integer composed of 2000 9s, and B is a 2000-bit integer composed of 2000 8s, so the sum of the digits of a×b is _ _ _ _ _ _ _.
8. Four consecutive natural numbers, from small to large, are multiples of 3, multiples of 5, multiples of 7 and multiples of 9, with the smallest sum.
It is _ _.
9. The charging standard for electricity consumption in a residential area is: the monthly electricity consumption of each household does not exceed 10 kWh, and the charge per kWh is 0.45 yuan; Exceeding 10 degrees without exceeding.
20 degrees, 0.80 yuan per degree; For the part exceeding 20 degrees, 1.50 yuan will be charged for each degree. Within one month, user A paid 7. 10 yuan more than user B.
If user B pays 3.75 yuan more than user C, then user A, user B and user C will pay _ _ _ _ _ _ _ _ _ _ _ _.
10. A car and a big truck met on a 9-kilometer-long narrow road, and they had to reverse the car to continue. As we all know, cars are very fast.
The speed of the truck is three times, and the speed of reversing the two cars is their own speed; The distance a car needs to reverse is four times that of a big truck. if
The speed of the car is 50 km/h, so it takes at least _ _ _ _ _ hours to cross this narrow road.
1 1. Grade five students in a school 1 10, take part in Chinese, math and English activity groups, and each student should take part in at least one group. Known participating language groups
52 people, only 16 people in the language group participated; 6 1 person participated in the English group, and only 15 people participated in the English group; There are 63 participants in the math group.
There are 2 1 people who only participate in the math group. Then there are _ _ _ _ _ people in all three groups.
12. There are eight steps, and Xiao Ming goes from bottom to top. If he can only take one or two steps at a time, he may go up in _ _ _ _ different ways.
1. Dongsheng Village will build a cuboid reservoir with a planned storage capacity of 720 tons. It is known that the pool is 18 meters long, 8 meters wide and at least how many meters deep? (1 m3 water weight 1 ton. )
A classroom is 8 meters long, 6 meters wide and 4 meters high. Paint the roof and four walls of the classroom. Excluding doors, windows and blackboards, the area is 26 square meters. How many square meters is the painting area?
A clothing factory used to use 3.8m cloth for uniforms. After improving the cutting method, each set saves 0.2 meters of cloth. Originally made 1800 sets of uniform cloth. How many sets can you make now?
4. Two cars, A and B, travel in opposite directions from two places, with a distance of 5 16 km. After driving for six hours, the repair of car B was suspended. At this time, the distance between the two cars is 72 kilometers. Two hours later, car A keeps the original speed and meets car B ... Find the speed of car B..
5. Make an uncovered rectangular water tank with iron sheet, which is 5cm long, 4cm wide and 3cm high. How much tin do you need at least?
Six baskets A, B and C contain several oranges respectively. There are 25 oranges in Basket A and Basket B. If/kloc-0 oranges are taken out of Basket A and put into Basket B and 4 oranges are taken out and put into Basket C, there are 3 oranges in Basket B and Basket C respectively. How many oranges are there in each of the three baskets?