There are 20 interesting math problems in junior high school urgently, thank you. Say as much as you

1.There is a natural number, and its sum with 168 is exactly equal to the square of a certain number; The sum of its 100 is in turn equal to the square of another number. Find this natural number.

2。Allen, Bart, Klay, Dick and Earl each played two tennis tournaments, and there will be no draw in each match. Here's the game info. :

1, only four games were played in each league, Allen vs. Bart, Allen vs. Earle, Klay vs. Dick, Klay vs. Earl 2, only one game remained the same in the two league wins and losses 3, Allen was the champion of the first league 4, in every league, losing one was eliminated, only the championship did not lose a game. Q, who is the winner of the second league?

3。Proof that: 1, the product of two numbers is greater than 75, and one of them must be greater than 8

2, the product of a two-digit number multiplied by five is also a two-digit number, then the number in the tenth place of this two-digit number is 1

4.Five people took part in the bike race, and after the race they said something like this.

The first person says that A is the second place and B is the third place.

The second person said that C was the third and D was the fifth.

The third person said that D was the first and C was the second.

The fourth person said that A was second and E was fourth.

The fifth person said that B was the first and E was the fourth.

It is now known that of the two sentences that everyone says, one is true and the other is false. Please find out the real match rankings.

5.Give you a code and see if you can decipher it.

e t w q

f w f q

a w q q q

Note: Uppercase letters represent numbers, and the same letters represent the same numbers. Decipher these three sets of numbers.

It would be a hassle to write down all the steps to solve the problem, sorry!

You can buy a book of Olympiad maths, there are a lot of them.

The two boys, each riding a bicycle, began riding in a straight line from two places 2o miles (1 mile or kilometer) apart. The moment they started, a fly on the handlebar of one bicycle began to fly straight towards the other. As soon as it reaches the handlebars of another bike, it immediately turns to fly backwards.

The fly so goes back and forth, flying back and forth between the handlebars of the two bikes until the two bikes meet. If each bike is traveling at an equal speed of 1o miles per hour, and a fly is flying at an equal speed of 15 miles per hour, how many miles have the flies flown in total?

The two boys were 20 miles apart, both at 10 miles per hour, and it took 1 hour when they met, and the fly flew at 15 miles an hour, and they flew for 1 hour, so they flew 15 miles.

Topic 12: A4 B6

Solve with the xy binary equation.

x+y=10 2x+3y=26 (A x B y) 3: The money should be divided into 260 divisors 1, 2, 4, 5, 10, 13, 20, 26, 52, 65, 130, 260. The sum of the years is 23, and assuming that the annual amount of money for women is 2a, then since the male has to be more, it is 3a, so even if all are female, 260 is equal to 46a; And even if it is all male, 260 is equal to 69a

Therefore, 46a<260<69a, a must also be 260 divisor, then a can only be 4, so each woman's annual remuneration is 8 yuan, men's is 12 yuan, and the total year is 23 years, and then the principle of chickens and rabbits in the same cage can find a total of 14 years for girls. In 2,3,5,6,7, only 2+5+7=14, so there are three women.

Question 18: Marlo is putting on makeup, Marder is reading, Marley is combing her hair, Marnie is manicure35:J is telling the truth.

Topic 2: ABCD

DCBA is still a four-digit figure because DCBA.

So A must be 1, otherwise ABCD 9 would not be a four-digit number.

And since the single digit of d 9 is 1, d must be 9

Write the equation as.

1 bc99cb 1

Because b 9 has no carry (otherwise a 9 carry product would not be a four-digit number), b must be 0 (because a=1).

And because the single digit of c 9 8 is 0, c must be 8

i.e. abcd=1089

Check: 1089 9 = 9801

Middle School Mathematics Chapter 3 Fun Equation B Synchronous Exercises and Answers.

Middle School Mathematics Chapter 3 Fun Equation B Synchronous Exercises and AnswersJunior High School Mathematics Chapter 3, Junior High School Mathematics Fun Questions Junior High School Mathematics Chapter 3 Fun Equation B Synchronous Exercises and Answers.

Fun math questions for junior high school.

.11. Fight in the water ( 12, from the last number ( 13, ten cents left ( 14, member ( 15, the number on the athlete's back ( 16, all annihilation ( junior high school math test questions, junior high school math competition test questions. 11, fighting in the water ( 12, from the last count ( 13, ten cents left ( 14, members ( 15, the number on the athlete's back ( 16, all annihilation (

Middle School Mathematics Chapter 3 Fun Equation A Synchronous Practice and Answers.

Middle School Mathematics Chapter 3 Fun Equation A Synchronous Practice and AnswersJunior High School Mathematics Chapter 3, Junior High School Mathematics Fun Questions Junior High School Mathematics Chapter 3 Fun Equation A Synchronous Practice and Answers.

Junior high school fun math questions b junior high school fun math questions, junior high school math fun practice questions junior high school fun math questions b see .

1.Xiao Wang ran from the first floor to the zoo to play, and saw the elephant standing there very leisurely. He suddenly thought of the story of Cao Chong weighing the elephant, and thought to himself that Cao Chong can weigh the elephant, can I measure the length of the elephant?

He frowned, took two pencils out of his pocket, held the short pencils in his hand and straightened his arm, and aimed his eyes at the ends of the pencils just in time to see the head and tail of the elephant. Then he changed his grip to a long pencil, aimed at the ends of the pencil and walked forward twenty paces, just in time to see the head and tail of the elephant again. He measured the length of his two pencils at 8 cm and 16 cm, and his arm was 40 cm long.

Each step is 50 cm long, and the elephant is quickly calculated to be 4 meters long. Xiaohua was very surprised and asked how did Xiaosan calculate it?

2.It takes 6 seconds to run to the fourth floor, and how many seconds does it take to run to the eighth floor at the same speed?

3.A group of children are siblings, and there are two siblings talking, and the younger brother says that he has one more brother than the number of sisters, so how many more brothers does the sister have than sisters?

4.Xiao Ming poured two-thirds of its volume into a tank with a base area of 24x18 cm and a height of 30 cm. He was a curious boy who wanted to know the volume of a lead block he had just bought.

After the lead block is placed in the tank, the water surface rises to 22cm, what is the volume of the lead block in cubic centimeters?

1.Use similar triangles to solve the problem:

Let the length of the elephant be x, the distance from the elephant for the first time is l1, and the distance for the second time is l2

Based on the knowledge of similar triangles, we get x 8=l1 40; x 16=l2 40, and because l1-l2=20*50=1000, l1=1000+l2

Combining the above three equations, we can get l2=1000Substituting l2=1000 into the equation yields x=4000

One dollar can buy a bottle of water, two empty bottles can be exchanged for a bottle of water, there are ten yuan, ask how many bottles of water can be drunk at most.

A: 20 bottles.

A number divided by 2 remainder 1 divided by 3 remainder 2 divided by 4 remainder 3 divided by 5 remainder 4 divided by 6 remainder 5

Find this number. Answer 59 119 179....Multiples of 6 are 1 less

1.When you ask for a few minutes, the box is half full.

Xiao Ming wanted to buy shoes, asked his parents to borrow a total of 300 yuan, spent 270 to buy shoes, the remaining 30, returned 20 to his parents, he left 10 yuan, and owed his parents 280, plus his ten yuan, a total of 290, where did the ten yuan go?

min 2Two days minutes 5Carlos is the biggest, Matthew is the smallest.

Is the answer to the first question 9 minutes?