A middle school has 4,200 students

1. There are x people in junior high school and y people in high school.

x+y=4200

x(1+solve the equation to get x=1400 y=2800

So now there are 1,400 students in junior high school and 2,800 students in high school.

2. If the loan of type A is X million yuan, and the loan of type B is y yuan, then.

x+y=35

Solve the equation to get x=20 y=15

Therefore, the amount of type A loan is 200,000 yuan, and the amount of type B loan is 150,000 yuan.

1. If there are x number of existing junior high school students, then high school students are (4200-x) people.

x(1 8%) 4200-x)(1 11%) = 4200 (1 10%) x = 1400 1400 junior high school students 2800 high school students.

2. Let A be x, then B is 35-x

7%x+6%(35-x)=

x=15 A 150,000 B 200,000.

A middle school has 4,200 students. A middle school has 4,200 students, and plans to increase the number of junior high school students by 8% in one yearAn 11 percent increase in high school enrollment would result in a 10 percent increase in the number of students enrolled in the school, Q:

The number of students enrolled in junior high school and high school at this school is now.

Set: X students in junior high school, 4200-x students in high school.

x=1400

The number of students enrolled in high school is 4200-1400=2800.

1. Junior high school student X, high school student Y

x+y=4200

Solution: x=1400

y=2800

2. A loan x, B loan y

x+y=35

Solution: x=15

y=20

Is this the question?

If there are thousands of students in a school (< 5,000), if all students are lined up in a line of 10, there will be 1 person left in the line; If you arrange it in a team of 9 people, there is still 1 left; Again, each person is lined up in line, and there is only one left at the end. Find the total number of students in the school (equation solution).

This is a matter of finding common multiples.

The total number of students in the school is x.

x-1=2*3*3*4*5*7*n (n is a positive integer) x=2520n+1

Since x is less than 5000, n 1

x=2521

A: The total number of students in the school is 2,521.

Hope, thank you.

Column equation: 373+x+y+377+370+z=2000;x 2000 = x = 380 from the question of the first and second high school a total of 1500 people, high school three for 500 people, stratified high school three should draw 48 * 500 2000 = 12 The third question: first for boys and girls to allocate 245 people, there are ten are not allocated, there are eleven distribution methods, of which equal accounts for 1 11 men more than women and women more than men each account for 5 11

There are 8 high schools and 22 junior high schools in a certain area To understand the vision of middle school students in the area, the random inspection in a, c, and d is not universal, and the selected objects are divided into different categories, so they are not representative

b. In order to understand the eyesight of middle school students in this area, 800 students were randomly selected from 30 middle schools in the area

Therefore, choose B

Let the junior high school student x person and the high school student y person get the binary system of equations: {x+y=4200

Let's figure it out for yourself.

This doesn't need a column equation, 10*7*9=630

630 is divisible by 6,630*4=2520, and 2520 is divisible by 8

The school has a total of 2,521 students.

There are x number of junior high school students this year.

There are (4200x) high school students.

Then there is the equation.

x×(1＋8％)＋4200－x)×(1＋11％)＝4200×(1＋10％)

According to the characteristics of the three sampling methods, if it is stratified sampling, the proportion of each segment should be 4 3 3, and the pants are suitable; If it is a systematic sampling, the sample number drawn by Moriharu should form an equal difference series with a tolerance of 27, and the first term should be less than or equal to 27The first of these items are 7 and 11, respectively, which are suitable; The first item is 30, which is not suitable. D. should be chosen

Junior high school student x, high school student y, x+y=4200 (1+8%)x+(1+11%)y=4200*(1+10%)solve binary linear equations, 1400 junior high school students, 2800 high school students.

Hello! Solution: Let's assume that the current number of junior high school students is x, and the number of high school students is y.

1+8%)x+(1+11%)y=4200×(1+10%)x+y=4200

Solution: x=1400, y=2800

A: The current number of junior high school students is 1,400 and the number of high school students is 2,800.

Solution: If this school now has x people in the junior high school, then the high school has (4200-x) people (1+8%) x + (1+11%) (4200-x) = 4200 (1+10%)

x=1400

High school: 4200-1400=2800 (person).

A: The school now has 1,400 students in the middle school and 2,800 in the high school.

There are now 1,400 in junior high school and 2,800 in high school.

1400*8%=112 people.

2800*11%=308 people.

112 + 308 = 420 people.

420 people = 4200 * 10%.

Let's take the current number of secondary school students to x

x*8%)+4200-x)*11%=4200*10%

There are x people in junior high school and y people in high school.

x y＝4200

1 8%） x （1 11%）y=4200×（1 10%）

x=1400y=2800 for the solution