Math Problem A problem from a farmer s uncle

Divide 100 into 8 bundles, each of which is singular, and then tie any 3 or 5 bundles together, so that there are 9 bundles in total, and each bundle is singular.

For example: 11 9 11 9 11 19 11 19 100, so it is 8 bundles, and then 11 9 9 are tied together. It's just one bundle, and there are many more.

Countless solutions, such as:

Divide 100 into 8 bundles, each of which is singular.

Then tie any 3 or 5 of them together, so that there are 9 bundles in total.

And each bundle is singular.

Bundle a single bundle, and then add a double on its periphery, which is another bundle, hehe, and the rest is simple.

When nine odd numbers are added, the sum must be odd.

11 in each bundle, and it is advisable to pick the remaining one.

11 in each bundle, and the remaining one is used to pick.

Countless solutions to bundle multiple bundles together are also called bundles.

No solution. When nine odd numbers are added, the sum must be odd.

18-(9+11+8-5-3-4)=18-16=2 people.

That is, there are 2 people with perfect marks in all three subjects.

Tie yourself up like a mallet.

The peasant uncle is uneducated, so he has this kind of question.

50 yuan, anyway, one person per acre, no matter how fast he is.

What is the relationship between sowing time and ploughing time?

1.Every number on the number has someone guessed correctly, if each person only guessed one number correctly, then only 3 numbers were guessed correctly, which does not fit the topic, so each person guessed 2 numbers correctly, 3 people guessed a total of 6 numbers correctly, but the original number is only 5 digits, so there are 2 people who guess the same number correctly, in the numbers 93715, 79538 and 15239, only the 3 on the ten digits appears 2 times, so there are 2 people who guess the number correctly.

And because the digits of the numbers that everyone guessed correctly are not adjacent, 79538 can only guess 7 or 9 correctly, 15239 can guess 1 or 5 correctly, and 93715 can only guess 7 and 5

This number is 75735 or 19735

Suppose the farmer turned out to have money x kopecks, and could make equations.

The money left after the first time was 2x-24

The money left for the second time was 2 (2x-24)-24

The money left for the third time is 0=2(2(2x-24)-24)-24)-24, and the third equation is solved to get x=21

Let it be x at the beginning. Then you have 2x-24 left after the first bridge crossingAfter the second bridge crossing it was 4x-48

After the third bridge crossing it was 8x-144And it's exactly equal to 24So 8x=168, so x=21

So there were 21 at the beginning

Set the farmer originally had x

First: 2x-24

The second time: 2 (2x-24) - 24 = 4 x - 24 * 3 The third time: 2 (4 x - 24 * 3) - 24 = 24

8x-24*6=24*2

8x=24*8

x=24

(24 2+24) 2+24) 2=21 (kopecks).

It's not easy to answer the question, and if you don't understand it, you can ask it, hope.

Solution: Let the peasants initially have x copper plates, according to the theme, get.

2[2(2x-24)-24]-24=0, and the solution is x=21

The farmer originally had 21 copper plates

Let the difficult problem be x, the medium question is y, and the easy question is z, because there are 100 problems in total, and the total number of problems solved is also 100, then there are no problems that have not been done, then.

x+y+z=100 ……Each person solved 60 of them, the medium problem was calculated 2 times if two people solved the addition, and the easy problem was calculated 3 times if all 3 people solved the addition.

x+2y+3z=180 ……2- Gotcha.

x-z=20, ie.

There are 20 more difficult questions than easy ones.

If the number of difficult questions is x and the easy problem is y, then the number of medium questions is 100-x-y

By definition, it is known that:

x only 1 person solves.

Y has 3 people to solve.

100-x-y is solved by only 2 people.

Then x+3y+2(100-x-y)=60*3=180, you can get x-y=20 after finishing it, so it is 20 more difficult questions than easy questions, and it is easy to understand that such questions draw three crossed circles.

No. 1 2 3 4 ——

A: 1—60

B: 20—80

C: 40—100

Difficult: 1-19 81-100 38 easy: 40-60 20.

38-20=18 (Dao).

There are more difficult and less easy, 20 more questions.

x+y+z=100

3x+2y+z=60*3

Equation 1 multiplies 2 by equation 2 to get z-x=20

Untie; 60*3=180

There are many easy questions, 40 more.

1) 6000 * 13% = 780 yuan 2) set the unit price of color TV is x yuan x + 2x + 600 = 6000 x = 1800, so the unit price of color TV is 1800 yuan, 4200 yuan for motorcycles, anonymous answer acceptance rate yuan, 2) set the unit price of color TV for x yuan x + 2x + 2x + 600 = 6000 x = 1800, so the unit price of color TV is 1800 yuan Motorcycle 4200 yuan.

The upside-down forty divine beasts packed up and packed up.

20 questions: easy questions, x questions, medium questions, y questions, difficult questions z, z-x, then x+y+z=100, z+2y+3x=180, so y=100-z-x

z+3x+200-2z-2x=180 x-z=-20 z-x=20

Suppose that only 1 person solves the number of problems x, 2 people solve the number of problems y, and 3 people solve the number of problems z, then the total number of problems solved by 3 people is:

x + 2y + 3z = 60* 3 ..1)

Removing the repetitive parts, the problem solved by the 3 people is:

x + y + z = 100 ..2)

2)*2 - 1) Available:

x-z=20, ie. "Puzzle"than"Easy"There are more than 20 questions

I have a question I want to ask, will there be some problems that the three students have not solved, what are these problems called?

Suppose there is a question A, a difficult question B, a medium question C, and a simple question D, then A+B+C+D=100 The three students completed the following questions: B+2C+3D=60*3

The questions that the three students did not complete are: 3a+2b+c=(100-60)*3

No solution. You have to make sure that there is no question that the three students have not answered.

Draw three intersecting circles.

The intersection of the three gardens is easy question x

Two circles intersect minus the easy problem is the medium problem 3y

The unintersecting part of the puzzle 3z

x+3y+3z=100 ..1）

x+2y+z=60 ..2)

Find 3z-x

1)-2）y+2z=40

2y+4z=80...3)

3)-2) 3z-x=20

Let easy question x, medium question, y problem, difficult question z, to z-x, then x+y+z=100 z+2y+3x=180, so y=100-z-x

z+3x+200-2z-2x=180 x-z=-20 z-x=20

Dizzy. Such a simple question is still asked. What grade are you in?

(250+150) 10=40 (m).

250 + 150) 100 = 4 (m).

Bus speed: (40 + 4) 2 = 22 (m).

Truck speed: 40-22 = 18 (m).

a=2x^2+3xy-2x-1,b=-x^2+xy-13a+6b=6x^2+9xy-6x-3-6x^2+6xy-6=15xy-6x-9

15y-6) x-9, because the coefficient of x is 0, so 15y-6=0, i.e. y=2 5