1. The fourth grade Olympic math problem for primary school students
1.42 students participated in tree planting, with an average of 3 trees planted by boys and 2 trees planted by girls, with 56 more trees planted by boys than girls. How many boys and girls are there? 2. A primary school held a math contest with *** 15 questions. He gets 8 points for every right question and 4 points for every wrong question. Xiaoming got 72 points in the exam. How many questions did he get right?
There are 25 questions in a test paper. Answer one question correctly and get 4 points. Answer correctly or not, get 1 point. A classmate * * * will get 60 points. He answered several questions correctly.
4. Xiaohua answers math judgment questions, giving 4 points for a correct answer and 4 points for a wrong answer. She answered 20 true and false questions and got only 56 points. She answered several questions wrong.
5. Yucai Primary School held a math contest in the fifth grade. There are *** 10 questions. She gets 8 points for each correct question, and 5 points for wrong questions. Zhang Xiaoling finally got 4 1 point. How many questions did she answer correctly?
6. I take some apples and pears to the nursing home every day to express my condolences. Take out two pears and four apples from the basket at a time and give them to the old man. Finally, the pear has just been eaten, and there are 27 apples left. At this moment, he remembered that there were three times as many apples as pears. How many apples and pears are there?
7. When 40 students did three math problems, 25 answered the first problem correctly, 28 answered the second problem correctly, and 365,438+0 answered the third problem correctly. So at least how many people answered three questions correctly?
8. A batch of sand and cement was brought into a construction site, with twice as many bags of sand as cement. Use 30 bags of cement and 40 bags of sand every day. After a few days, all the cement was used up, leaving 120 bags of sand. How many bags of sand and cement are there?
9. The school bought five thermos bottles and 10 teacups, which cost 90 yuan. The price of each thermos is four times that of each teacup. How much is each thermos and teacup?
10, the sum of the two numbers is 572, and one of the digits is 0. After removing 0, it is the same as the second addend. What are these two numbers?
2. Primary school students' fourth-grade Olympic math problems
1. There are 340 peach trees and apricot trees planted in the orchard, of which the number of peach trees is 20 times more than that of apricot trees. How many trees have been planted? 2, a rectangle, 30 cm in circumference, twice as long and wide. Find the area of this rectangle.
3. Two numbers, A and B. If A plus 320 equals B. If B plus 460 equals three times that of A, what are these two numbers?
There are two pieces of cloth with the same length. The first piece sells for 25 meters, the second piece sells for 14 meters, and the remaining piece of cloth is twice as long as the first piece. How many meters is each piece of cloth?
There are 150 peach and pear trees in the orchard. There are 20 more peach trees than pear trees. How many fruit trees are there?
6. Two barrels of oil from Party A and Party B weigh 30 kilograms. If 6 kilograms of oil in barrel A is poured into barrel B, the weight of the two barrels of oil is the same. How much oil is there in barrels A and B?
7. Both brothers are 30 years old this year. When the elder brother is the same age as the younger brother, the younger brother is exactly half his age. How old is my brother this year?
8. The mother and daughter are 64 years old, and the daughter is three years older than her mother. How old are the mother and daughter?
9. My brother is older than Xiaoli this year 12 years old. Eight years ago, my brother was four times older than Xiaoli. How old are they this year?
10. Grandpa is 72 years old and grandson is 12 years old. A few years later, grandpa was five times as old as his grandson. A few years ago, my grandfather was 13 times older than my grandson.
3. Primary school students' fourth-grade Olympic math problems
1. Connect the thick steel pipe to the thin steel pipe. If two thin steel pipes are connected, the length is 18m, and if five thin steel pipes are connected, the length is 33m. How long is a thick steel pipe and a thin steel pipe? 2. The cement plant originally planned to complete the task within 12 days, because it produces more cement every day. 8 tons, as a result, the task was completed in 10 days. How many tons of cement was originally planned to be produced every day?
The school held a song and dance party, and 80 people took part in the performance. Among them, there are 70 singers and 30 dancers. How many people are singing and dancing?
4. There are 59 students in Class One, Grade Three, 36 students in Chinese competition, 38 students in math competition, and 5 students who have never participated in any subject. How many people attended these two courses?
The school bought four tables and six chairs, and used 640 yuan. The price of two tables and five chairs is equal. What is the unit price of each desk and chair?
6. My father is 45 years old. Five years ago, his father was four times as old as his son. How old is his son this year?
7. There are two barrels of oil, and the weight of barrel A is four times that of barrel B. If 18kg of barrel A is poured into barrel B, the weights of the two barrels of oil are equal. How many kilograms is there in a barrel of oil?
8. bright primary school held a math knowledge contest with 20 questions. Answer a question correctly and get 5 points; Answer a wrong question, deduct 3 points; No answer, 0 points. Xiao Li got 79 points. How many questions did she answer correctly and wrongly? How many questions did she leave unanswered?
9. Train A is 240 meters long and travels 20 meters per second; Train B is 264 meters long and runs at a speed of 16 meters per second. Two cars face each other. How many seconds does it take from the meeting of two heads to the separation of two tails?
10. A train is 600 meters long and passes through a tunnel with a length of 1 150 meters. As we all know, the speed of the train is 700 meters per minute. How many minutes does it take for the train to cross the tunnel?
4. Primary school students' fourth-grade Olympic math problems
1. Weight of a barrel of oil16kg. After half use, the barrel weighs 9 kilograms. How many kilometers does this bucket weigh? 2. Weight of a barrel of oil 10 kg. After pouring out half, the barrel weighs 5.5 kilograms. How many kilograms of oil are there?
3. Pump water with a bucket, and increase the water volume by twice. The weight of the bucket is 10 kg. If the water is increased to five times, the weight of the bucket is 22 kilograms. How many kilograms of water are there in the bucket?
Xiaohong and Xiaohua have 36 story books. If Xiaohong gives Xiaohua five books, they have the same number of story books. How many books do Xiaohong and Xiaohua have?
There are five barrels of oil with the same weight. If 15kg is taken out of each barrel, the weight of the remaining oil in five barrels is exactly equal to the weight of the original two barrels. How much does a barrel of oil weigh?
6. It takes 9 minutes to saw a piece of wood into 3 sections, so how many points does it take to saw this piece of wood into 5 sections at the same speed?
7. In a workshop, there are 35 fewer women workers than men. 17 after the transfer of male and female employees, the number of male employees is twice that of female employees. How many people are there? How many women workers are there?
8. Li Qiang rides a bike from place A to place B at a speed of 12km, and it takes five hours to get there. It took 1 hour to return from B to A because of the headwind. How many kilometers does he drive per hour on average?
9. Party A and Party B walk from two places which are 18km apart, with Party A walking 5km per hour and Party B walking 4km per hour. If A starts with a dog and A at the same time, the dog runs to B at a speed of 8 kilometers per hour. When it meets B, it immediately runs back to A, and when it meets A, it flies back. How many kilometers did the dog run when they met?
10, with red, yellow and white balls, red and yellow balls 2 1, yellow and white balls 20, red and white balls 19. How many balls are there in each of the three kinds?
5. Primary school students' fourth-grade Olympic math problems
1, Xiaoming goes to school from home. If he walks 50 meters per minute, it's time for class. If you walk 60 meters per minute, there are still 2 minutes before class time. How far is it from home to school? There is a circular runway with a circumference of 600 meters. A and B go in the same direction at the same time. A runs 300 meters per minute, and B runs 400 meters per minute. How many minutes did they meet for the first time?
3. There is a rectangular cardboard. If the length is only increased by 2 cm, the area will increase by 8 square meters; If the width is only increased by 2cm, the area will increase by 12cm2. What is the original area of this rectangular cardboard?
Mom bought 3 kilograms of apples and pears, paid 20 yuan and got 7 back. 4 yuan. 2 apples per kilogram. 4 yuan, how much is a catty of pears?
5. Party A and Party B walk towards each other at the same time from two places with a distance of 135km, and meet each other after 3 hours. A is twice as fast as B. How many kilometers do A and B walk per hour?
There are the same number of black balls and white balls in the box. Take out eight black balls and five white balls at a time. After taking it out several times, the black ball disappeared, leaving 12 white ball. How many times does a * * * shoot? How many balls are there in the box?
7. At six o'clock in the morning, Basino. 1 and 2 buses will leave from the bus station at the same time. Basino. 1 every 12 minutes, and bus No.2 every 18 minutes. Please ask the time of the next simultaneous departure.
8. The father is 45 years old and the son 15 years old. How many years ago, the father's age was 1 1 times that of his son?
9. Miss Wang has a box of pencils, such as 1 2 students, 2 3 students, 3 4 students and 4 5 students. How many pencils are there in this box?
10, a parallelogram, if the base is only increased by 8 meters or the height is only increased by 5 meters, its area will be increased by 40 square meters. Find the original area of this parallelogram?