Fifth-grade math problem

1. fifth grade mathematics knowledge smile.

The fifth grade mathematics knowledge joke 1. Fifth grade math jokes

There are many of them. I'll give you some excerpts to see if it's 1. The arithmetic teacher said, "Here are 10 pears. I ate six, how many are left? " A greedy student replied, "I think we should eat the rest together."

Zaizai came back from school happily and asked his mother, "Where is Dad?" Mother saw Zaizai's excitement and asked strangely, "Is Dad at home? What do you want with dad? " "I asked my father for fifty cents." "Why?" Mom asked.

"Before taking the math test, my dad told me,' If I get a score of 100, I'll get 1 yuan, and 80 will be given to 8 cents.' Today, I got 45 points in math.

"Aberdeen replied. My mother was surprised and asked, "What! Only 45 points in math? Zaizai proudly said, "Yes, it takes 4 points to give up math, and 5 points for math, so dad has to pay 50 points." "

A well-dressed girl walked into the remittance office of the post office, filled out the money order and handed it to the clerk. When the clerk saw it, he returned the bill and said, "The figures should be capitalized."

The girl cocked her head and said, "Capitalized? The grid is so small, how can I write big? " 4. "Dad, the No.4 bus is coming!" "Fool, that's not No.4, it's No.31!" "The teacher said, 3+ 1=4!" The little boy said confidently. I hope I can help you, wish you progress in your study, and travel and grow happily in the world of mathematics.

2.5 grade mathematics knowledge

A math joke 1. Once, her mother patiently inspired her to do arithmetic: "Ya Ya, have you learned to do subtraction?" Come on, let's see, how much is 4 MINUS 2? ""it's already two o'clock, mom. "

"That's right, good boy. So, what about 5 MINUS 5? " "Five minus five, minus five.

"Ya ya muttered," I won't, mom. "

"Son, you can't! Think about it, for example, you have five coins in your pocket, but suddenly, all five coins fall out. Tell me, what else do you have in your pocket? " Ya Ya blinked her eyes and said, "Did you drop it? Well, there is still a hole in my pocket! " "I always get 100 in arithmetic."

"That's because you learn well." "But I never listen in class."

"That's because you are smart. You will know to study hard when you come home from school." "Smart? A little, but after school, I am a person who deals with football. "

"Then you must have cheated in the exam." "I can't say that. I didn't copy books or peek at others. How can I be derailed? "

"Then what happened to you?" "I kicked Jim, the bookworm in front, in the chair." "If you don't, you won't. How can you be so naughty? "

"I kicked the first foot, and he stretched five fingers back with his hand." "What does this mean?" "The answer to the first question is 2+3."

"Oh ... what if you ask the 5*8 answer to the tenth question?" "It was after I kicked the tenth foot that he stretched out four fingers first and then clenched his fist immediately, so I knew the answer of 40." 3. The teacher announced the results: "Xiaohua scored 30 points, Xiaoming scored 20 points ..." Pig: I got 0 points! Dog: What should I do? Me too ... Pig: We both got the same score in the exam. Will the teacher think we cheated? Legend has it that one day, Zhuge Liang summoned his soldiers and said, "Which one of you chooses an integer from 1 to 1024 and keeps it in mind. I asked ten questions, only one' yes' or' no'.

After answering all ten questions, I will' calculate' the numbers in your mind. "ZhuGeLiangGang say that finish, a counselor stood up and said, he has chosen a good number.

Zhuge Liang asked, "Did you choose more than 5 12?" The counselor replied, "No." Zhuge Liang asked his advisers nine questions in succession, and all the advisers answered them one by one.

Zhuge Liang finally said, "The number you remember is 1." The counselor was surprised because he really chose this number.

Do you know how clever Zhuge Liang is? In fact, the method is very simple, that is, take half of 1024, and the tenth time is "1". According to this truth, you can find the required number by asking ten questions in a row.

3. Mathematical sayings 1. Wang Juzheng's Percentage China scientist Wang Juzheng has a proverb about experimental failure, which says, "There is still a 50% chance of success if you continue, or 100% failure if you don't do it." 2. Tolstoy's score When it comes to people's evaluation, Tolstoy compares people to a score.

He said: "A person is like a score, his practical ability is like a numerator, and his evaluation of himself is like a denominator. The larger the denominator, the smaller the value of the score. "

1, the essence of mathematics is its freedom. Cantor) 2. In the field of mathematics, the art of asking questions is more important than the art of answering questions. Cantor) 3. No problem can touch people's emotions as deeply as infinity, and few other concepts can stimulate reason to produce rich thoughts as infinity. However, no other concept needs clarification like infinity. Hilbert) 4. Mathematics is an infinite science. Hermanville 5. The problem is the core of mathematics. P.R. halmos 6. As long as a branch of science can ask many questions, it is full of vitality. No problem, indicating the termination or decline of independent development. Hilbert 7. Some beautiful theorems in mathematics have such characteristics: they are easy to sum up from facts, but the proofs are extremely profound. Gauss 3. Rybakov's Constants and Variables Russian historian Rybakov said in The Use of Time: "Time is a constant, but for diligent people, it is a' variable'. People who use' minutes' to calculate time spend 59 times more time than people who use' hours'. "

When talking about learning and exploration, Hua, a famous mathematician in China, pointed out: "To dare to do subtraction in learning is to subtract the parts that have been solved by predecessors and see if there are any unsolved problems, which need us to explore and solve." Edison, a great inventor, used a plus sign to describe genius. He said: "Genius = 1% inspiration +99% sweat."

6. dimitrov's symbol dimitrov, an internationally renowned worker movement activist, said in his evaluation of a day's work: "We should spend time thinking about what we have done in a day, whether it is' addition' or' subtraction'. If it is' addition', we will make progress; If it is'-',you have to learn from it and take measures. " 3. The aphorism written in Formula 7. Einstein Formula When talking about the secret of success, Einstein wrote a formula: A = X+Y+Z Y+Z.

And explained: A stands for success, X stands for hard work, Y stands for correct method, and Z stands for less empty talk. ""If you use a small circle to represent what you have learned and a big circle to represent what I have learned, then the area of the big circle is a little more, but the blank outside the two circles is our ignorance.

The bigger the circle is, the more ignorant faces its circumference contacts. "-Zhi Nuo Cauchy (A.L. Cauchy) People will die, but their actions will last forever. People will die, but achievements will last forever.

Laplace (1749–1827) is not well known. What we don't know is infinite. C. Hermite1822–1901) Abel left mathematicians enough to keep them busy for 500 years. When commenting on Abel, he once said: "What Abel left behind can keep mathematicians busy for 500 years.

"Poursin (Poisson, Simé on1781-1840)" Life is only good for two things, namely, discovering mathematics and teaching.

3.5 grade math jokes

1, unreasonable arithmetic

The arithmetic teacher said, "Here are 10 pears. I ate six, how many are left? " A greedy student replied, "I think we should eat the rest together."

2, rounding

Zaizai came back from school in high spirits and asked his mother, "Where's Dad?" Mother saw Zaizai's excitement and asked strangely, "Is Dad at home? What do you want with dad? " "I asked my father for fifty cents." "Why?" Mom asked. "Before taking the math test, my dad told me,' If I get a score of 100, I'll get 1 yuan, and 80 will be given to 8 cents.' Today, I got 45 points in math. "Aberdeen replied. My mother was surprised and asked, "What! Only 45 points in math? Zaizai proudly said, "Yes, it takes 4 points to give up math, and 5 points for math, so dad has to pay 50 points." "

Step 3 capitalize

A fashionable girl walked into the remittance office of the post office, filled out the money order and handed it to the clerk. When the clerk saw it, he returned the bill and said, "The figures should be capitalized." The girl cocked her head and said, "Capitalized? The grid is so small, how can I write big? "

4. There is nothing wrong.

Min Min: "How to write 7+3= 10, 7+3= 1?" Baby: "I just didn't write 0 at the end!" " Min Min: "That's wrong! "The baby said," 0 doesn't mean anything. "

5. Wu Zetian

In history class, the teacher asked, "Who knows who Wu Zetian is?" Student: "Wu Zetian is a mathematician. Five days later, she will be the great mathematician who invented rounding."

Step 6 wait for the bus

"Dad, the No.4 bus is coming!" "Fool, that's not No.4, it's No.31!" "The teacher said, 3+ 1=4!" The little boy said confidently.

7. That's the difference.

Teacher Fang asked Axi in math class, "What's the difference between one-half and one-eighth?" Asi didn't answer. Teacher Fang said, "Think about it. If you had to choose half an orange or eight sixteenth oranges, which one would you choose? " Axi: "I must have half." "Why?" "A lot of orange juice has been squeezed dry when the oranges are divided into one sixteenth, don't you think so, teacher?"

8. Checking calculation

During the exam, a student took out the dice and shook out ten multiple-choice answers.

At last he suddenly took it out and shook it.

The invigilator finally couldn't bear it: "What are you doing?"

The student replied, "I'm checking."

9, rounding

Zaizai came back from school in high spirits and asked his mother, "Where's Dad?" Mother saw Zaizai's excitement and asked strangely, "Is Dad at home? What do you want with dad? " "I asked my father for fifty cents." "Why?" Mom asked.

"Before taking the math test, my dad told me,' If I get a score of 100, I'll get 1 yuan, and 80 will be given to 8 cents.' Today, I got 45 points in math. "Aberdeen replied.

My mother was surprised and asked, "What! Mathematics is only 45 points? " Zaizai proudly said, "Yes, it has to be rounded off mathematically, so Dad has to pay 50 cents."

10, multiplication table The teacher found a student's name in the exercise book: Mu (1+2+3).

The teacher asked, "Whose exercise book is this?" A student stood up and said, "It's mine!" Teacher: "What's your name?" Student: "Mulinsen!" Teacher: "Then how did you write your name like this?" Student: "I used multiplication and division!" " "

4. Math jokes suitable for fifth-grade students

1. Mom went home and asked Xiao Ming, "How was the math test? Xiao Ming said, "Yes, there is a saying that you can't do arithmetic. It asks 3*7=? I wrote a 15 regardless of the willy-nilly. "

2. 1 Say to 4: Pay attention! 9 to 6: Are you tired of thinking about this all day? 9 said to 0: Don't think that cutting the tail is character! 1 Say to 7: Brother, when did your waist break?

A statistician met a mathematician, and the statistician teased the mathematician and said, "Didn't you say that if X=Y and Y=Z, then X=Z! Then I think if you like a girl, then you will also like the boy that the girl likes? "

The mathematician thought for a moment and asked, "Then you put your left hand in a pot of 100 degree boiling water and your right hand in a pot of 0 degree ice water." ! Because they are only 50 degrees on average! "

I'm going to be deformed

Math teachers are often used to saying to distracted students in class, "Pay attention! I want to ... "

One day, while explaining the equation, he found another student distracted, so he snapped, "Be careful, I'm going to be deformed!" " "

The spirit of all beings does it one brace up, and dozens of pairs of eyes stare at him. ...

Professor of mathematics

A math professor was knocked down by a speeding car on the road, and the driver left without stopping. When the traffic police came to ask about the license plate number of the car, the professor thought for a moment and said, "At the moment when I was knocked down, I only saw an equation on the car: XY minus 5 17, and the final difference was 24 ..."

Wu Zetian is a great mathematician.

History teacher: "Do you know who Wu Zetian is?"

Student: "Wu Zetian is a mathematician. Adding it after five is the great mathematician who invented rounding. "

5. Knowledge points of mathematics in the fifth grade of primary school

Summary of the knowledge points reviewed at the end of the first volume of mathematics in the fifth grade of primary school Unit 1 Decimal multiplication 1, decimal multiplication integer (p2,3): meaning-a simple operation to find the sum of several identical addends.

For example, 1.5*3 indicates how many times 1.5 is or the sum of three 1.5. Calculation method: first expand the decimal into an integer; Calculate the product according to the law of integer multiplication; Look at how many decimal places the factor has, and count the decimal places from the right of the product.

2. Decimal times decimal (P4, 5): that is, what is the score of this number. For example: 1.5*0.8 is eight tenths of 1.5.

1.5* 1.8 is 1.8 times 1.5. Calculation method: first expand the decimal into an integer; Calculate the product according to the law of integer multiplication; Look at how many decimal places the factor has, and count the decimal places from the right of the product.

Note: In the calculation results, the 0 at the end of the decimal part should be removed to simplify the decimal; When the number of decimal places is not enough, use 0 to occupy the place. 3. Rule (1)(P9): the product of a number (except 0) multiplied by a number greater than 1 is greater than the original number; A number (except 0) is multiplied by a number less than 1, and the product is less than the original number.

4. There are generally three methods to find the divisor: (P 10) (1) rounding method; (2) into law; (3) Truncation method 5. Calculate the amount of money, and keep two decimal places, indicating that the calculation has reached the point. Keep one decimal place, indicating that the angle has been calculated.

6. The operation of (p11) four decimal places is the same as that of an integer. 7. Algorithm and nature: addition: additive commutative law: a+b=b+a addition rule: (a+b)+c=a+(b+c) subtraction: subtraction nature: a-b-c=a-(b+c) a-(b-c)=a-b+c multiplication: C. The significance of fractional division: knowing the product of two factors and one of them, and finding the operation of the other factor.

For example, 0.6÷0.3 means that the product of two known factors is 0.6, and one factor is 0.3 to find the other factor. 9. Calculation method of decimal divided by integer (P 16): decimal divided by integer and then divided by integer.

The decimal point of quotient should be aligned with the decimal point of dividend. The integer part is not divided enough, quotient 0, decimal point.

If there is a remainder, add 0 and divide it. 10, (P2 1) The calculation method of division in which the divisor is a decimal number: first expand the divisor and the dividend by the same multiple to make the divisor an integer, and then calculate according to the rule of fractional division in which the divisor is an integer.

Note: If there are not enough digits in the dividend, make up the dividend with 0 at the end. 1 1, (P23) In practical application, the quotient obtained by fractional division can also be rounded to a certain number of decimal places as needed to obtain the approximate value of the quotient.

Division change of 12, (p24,25): ① Quotient invariance: divisor and divisor expand or shrink by the same multiple (except 0) at the same time, and the quotient remains unchanged. (2) The divisor remains the same, the dividend expands, and the quotient expands.

③ The dividend is constant, the divisor decreases and the quotient expands. 13, (P28) Cyclic decimal: the decimal part of a number. Starting from a certain number, one number or several numbers appear repeatedly in turn. Such decimals are called cyclic decimals.

Circular part: the decimal part of a circular decimal, which is a number that appears repeatedly in turn. For example, the cyclic part of 6.3232 ... is 32. 14, and the number of digits in the decimal part is a finite decimal, which is called a finite decimal.

The number of digits in the decimal part is infinite decimal, which is called infinite decimal. Unit 3 Observing the object 15, observing the object from different angles may lead to different shapes; When observing a cuboid or cube, you can see at most three faces from a fixed position.

Unit 4 Simple Equation 16, (P45) In a formula containing letters, the multiplication sign in the middle of the letters can be written as "?" , can also be omitted. The plus sign, minus sign, division sign and multiplication sign between numbers cannot be omitted.

17, a*a can write a? A or a, a is pronounced as the square of a, and 2a stands for a+a 18. Equation: An equation with an unknown number is called an equation.

The value of the unknown that makes the left and right sides of the equation equal is called the solution of the equation. The process of solving an equation is called solving an equation.

19, principle of solving equation: balance. The equation still holds when the left and right sides of the equation add, subtract, multiply and divide the same number (except 0) at the same time.

20, 10 quantitative relationship: addition: sum = addend+addend = and-two addend subtraction: difference = minuend-Mei Mei = difference+Mei Mei = minuend-difference multiplication: product = factor * factor = product ÷ another factor division: quotient = 22, equation testing process: = ... a calculation process of solving equations.

= the right side of the equation, so X=… is the solution of the equation. Unit 5 Polygon area 23, formula: rectangle: perimeter = (length+width) * 2- length = perimeter ÷2- width; Width = perimeter ÷2- long letter formula: C=(a+b)*2 area = length * wide letter formula: S=ab square: perimeter = side length *4 letter formula: C=4a area = side length * side length letter formula: S = parallelogram area = bottom * high letter formula: S=ah triangle. Height = area *2÷ letter formula: S=ah÷2 trapezoidal area = (upper bottom+lower bottom) * height ÷2 letter formula: S =(a+b)h÷2- upper bottom = area *2÷ height-lower bottom, lower bottom. Height = area *2÷ (upper bottom+lower bottom) 24. Derivation of parallelogram area formula: shear and translation 25. Derivation of triangle area formula: rotating parallelogram can be transformed into rectangle; Two identical triangles can be combined into a parallelogram, and the length of the rectangle is equivalent to the base of the parallelogram; The base of parallelogram is equivalent to the base of triangle; The width of the rectangle is equivalent to the height of the parallelogram; The height of parallelogram is equivalent to the height of triangle; The area of a rectangle is equal to that of a parallelogram and twice that of a triangle. Because the area of a rectangle is equal to the length * width, and the area of a parallelogram is equal to the bottom * height.

Because parallelogram area = base * height, triangle area = base * height ÷226, the derivation of trapezoid area formula: rotation 27, the second derivation of triangle and trapezoid.

6. All knowledge points of fifth grade mathematics

Grade 5 Mathematics Book 10 Final Examination Paper Result: 1. Fill in the blanks: 20% 1. 2.5 hours = () hours () minutes 5060 square decimeters = () square meters. Divider of 2. 24 is (), and the prime factor of decomposition 24 is (). 3. The decimal unit is the maximum value of 1/8.

4. The numerator of the simplest fraction is the smallest prime number, the denominator is the composite number, and the maximum fraction is (). If you add decimal units like (), you will get 1. 5. Cut a cuboid whose length, width and height are 5 decimeters, 3 decimeters and 2 decimeters respectively into two small cuboids, and the maximum sum of the surface areas of these two small cuboids is () square decimeters.

6. With a 52 cm long wire, you can weld it into a rectangular frame. The frame is 6 cm long, 4 cm wide and () cm high.

7.A = 2 * 3 * 5, B = 3 * 5 * 5, the greatest common divisor of A and B is (), and the smallest common multiple is (). 8. When the side length of a cube is enlarged by 3 times, its surface area is enlarged by () times and its volume is enlarged by () times.

9. Compared with 5/ 1 1, () has a larger decimal unit and a larger fractional value. 10. The greatest common divisor of two numbers is 8 and the least common multiple is 48, where one number is 16 and the other number is ().

Second, multiple-choice questions (fill in the serial number of the correct answer in brackets): 20% 1. In the following formula, the divisible formula is () 14 ÷ 8 = 0.5239 ÷ 3 =1335.2 ÷ 2.6 = 2 2. Fractions that can be converted into finite decimals are ()13,22,31. 3. The product of the multiplication of two prime numbers must be () 1 addend 2, even number 3 and composite number 4. A = 5b (both A and B are non-zero natural numbers) The following statement is incorrect: ()1The greatest common divisor of A and B is the least common multiple of A2A and B, and A3A is divisible by B, and A contains about 5 5. Add 10g salt into 10g water, and the salt accounts for () ①1/9②110③116. Given A&B, compare 2/a with 2/b () ① 2/a >; 2/B22/A7。 The greatest common divisor of two numbers is 12, and the common divisor of these two numbers is () 122436. 8. Dig out a cuboid with a small piece (as shown). The following statement is completely correct: () ① The volume decreases and the surface area decreases; ② the volume increases; ③ The surface area remains unchanged. 9. To spell a square, you need at least this rectangular piece of paper ().

14, 26, 38, 10, and a 6-meter-long rope. Cut 1/2 first, then 1/2 meters. At this time, there is still ()15m, 25/2m and 30m. 3. Calculation problem: 28% 1. Find the surface area and volume of a cuboid (unit: decimeter) 4% a=8 b=5 c=4 2. Off-model calculation (simplified) 12% 6/7+2. 1519/21+5/7-3/142/3+5/9-2/3+5/98/9-(1/4-/kloc) What's this number? (solved by equation) 4. 4% of the drawing problems, please use shading to indicate 1/2 (at least 5 kinds). 5. Application problem: 30% 1. A piece of land, including 1/5 kinds of corn, 1/6 kinds of vegetables, and the rest kinds of watermelons. What is the proportion of watermelons planted in this land? There are 24 boys and 20 girls in one class. How many times more boys than girls? What is the percentage of boys to girls? Students take part in environmental protection action.

The fifth grade cleared 3/5 tons of garbage, less than the sixth grade 1/8 tons. How many tons of garbage were removed in grade five or six? 4. A rectangular iron plate with a length of 40 cm and a width of 30 cm, the four corners are cut off and the sides are 4 cm long, and then welded into a box without a cover.

How many liters is its volume? 5. A car travels192km in the first 3 hours and 58km per hour in the last 2 hours. What is the average speed of this car? .

7. The fifth grade math story

1. Xiaohua's father can cut off five of his own nails in 1 minute. How many nails can he cut in five minutes?

Xiaohua took 50 yuan's money to the store and bought a car worth 38 yuan, but the salesman only gave him 2 yuan money. Why?

Xiaojun said: "I went fishing yesterday and caught a tailless fish, two headless fish and three half-baked fish." Guess how many fish I caught? " Students, guess how many fish Xiaojun caught?

4.6 horses and a cart ran six miles. How many miles did each horse run? How many miles did six horses run?

5. A puppy tied to a tree trunk greedily eats a bone on the ground, but the rope is not long enough, which is 5 cm shorter. How do you teach dogs to scratch bones?

6. Wang walks from place A to place B. 1 minute later, Li walks from place B to place A. When Wang and Li meet on the road, who is farther from A?

7. The clock just struck 13. What should you do now?

8. On the vast grassland, there is a cow eating grass. This Niu Yi only ate half of the grass on the grassland in 2008. Q: How many years does it take to eat all the grass on the lawn?

9. Mom has seven pieces of candy. She wants to give them to the three children equally, but she doesn't want to cut the remaining candy. What should mom do?

10. There is a row of trees along the road in the park, and the distance between each tree is 3 meters. What is the distance between the first tree and the sixth tree?

1 1. Divide 8 in half, as shown below. How much is each half? The average score of arithmetic method is _ _ _ _ points, from which the horizontal score is _ _ _ _ points, and from which the vertical score is _ _ _ _ _ points.

12. A house has four corners, one corner has a cat, and there are three cats in front of each cat. How many cats are there in the room?

13. The house has four corners. There is a cat in a corner. There are four cats in front of each cat. How many cats are there in the room?

14. Xiaojun, Xiaohong and Xiaoping played chess, and played 3 sets altogether. Ask them how many games they played. (Every chess game is played by two people)

15. Xiaoming and Xiaohua each have a bag of sweets, but I don't know how many pieces there are in each bag. I only know that after Xiaoming gave Xiaohua 8 yuan, Xiaohua gave Xiaoming 14 yuan. At this time, the amount of sugar in their bags is exactly the same. Students, who do you think has more sugar? How much more?

Answer:

1.20, including fingernails and toenails.

2. Because he paid the salesman 40 yuan, he only gave him 2 yuan;

3.0, because the fish he caught does not exist;

4.6 Li, 36 Li;

Just teach the puppy to turn around and grab the bone with its hind feet.

6. They were in the same place when they met, so they were as far away from A;

7. This clock should be repaired;

8. It will never eat all the grass, because the grass will always grow;

9. Mom eats one piece first, and then gives two pieces to each child;

10. 15m；

1 1.4,0,3.

12.4;

13.5;

14.2 disk;

15. It turns out that there are many florets; 14-8=6 pieces, because the number of candy pieces of two people is exactly the same, so the result is that there are more small flowers than Xiaoming 12 pieces.