I was stumped by the math problem in the first year of junior high school and asked for help

1.What's the problem? Can't understand your question.

2.It must be a loss, and these two tops are A and B respectively (from the question, you can know that A and B are not equal), so how is the profit calculated? It is the selling price - cost = profit.

Profit margin is the cost of profit. So, let's compare the size of the profit backwards. A shirt makes a profit of 25%, then the cost of A must be less than the selling price of A, right, then in the same way, the cost of B must be greater than the selling price of B.

And they sell for the same price, so the cost of A must be less than the cost of B. So who is the bigger profit of cost A * 25% or cost B * 25% of the loss? B., of course

So it must be a loss. As for how much to lose, how much to earn, you make an equation and come out. It is important to note that their costs are absolutely different, otherwise how can there be profits and losses.

3.Just find the equivalence relation.

Equivalence relationship: number of boys x * average score of boys 10 11y + number of girls 10 11x * average score of girls y

Number of boys x + number of girls 10 11x

The average score of girls is 10 per cent higher than that of boys, and the average score of girls is 10 per cent higher than that of boys, and the average score of girls is 10 per cent higher than that of girls

I'm setting the number of boys to be x and the average number of girls to be y.

Don't be afraid to have XY, you can simplify it. Finally, it is calculated that x=84 y=. Then you can calculate the average score of the boys.

I'm tired of beating.。。。

1.The answer is 36

Reason: a+b+a+c+a+d=66

a+b+c+d）+2a=66

a+b+c+d=66-2a

Compare a+b=20,a+c=24,a+d=22,, if a takes 23 and a+b=20, a+d=22 contradicts, if a takes 21 and a+b=20 contradicts, so a can only take 19 at the maximum, because a is a positive integer, so he takes 1 at the minimum

Then m=a+b+c+d=66-2a=66-2*1=64

n=a+b+c+d=66-2a =66-2*19=28

m-n=64-28=36

2.Lost 18 yuan.

x* x=108

y* y=180

x y-135*2=288-270=18

If the average score of girls is x and the number of girls is a, then the total score of girls is x*a

The average score of the boys should be x*10 11, the number of boys should be x*a, and the total score of the boys should also be x*a

Therefore, the total score of a school team is the total score of girls + the total score of boys = (x*a + x*a) = 2x*a

The total number of boys and girls is:

Therefore, the average score of the team is the total number of students = 2x*a, and the number of girls is divided into a, then, x=, that is, the average score of the girls and the average score of the boys is the score.

1. From a + b = 20, a + c = 24, a + d = 22 to get b minimum = 1, c maximum is equal to 23, a maximum is equal to 19When A is maximum, B = 1, C = 5, D = 3, n = 19 + 1 + 3 + 5 = 28, and when C is maximum, A = 1, B = 19, D = 21, M = 1 + 19 + 23 + 21 = 64, M - N = 64-28 = 36

2. Profit: x*(1+25%)=135 x=108 Loss: y*(1-25%)=135 y=180 108+180-135*2=18 So the loss is 18 yuan.

3. If the number of girls is x and the average score of boys is y, then x* solution gets y=84, that is, the average score of boys is 84 points, and the average score of girls is 84*(1+10%)=

Wow,It's not the first year of junior high school at all, right?=

It must have been from that rubbish summer homework.

Not beat around the bush. It's too much trouble to hit the steps.

Too lazy to fight.

I was a sophomore, and I didn't even know how to be a freshman in junior high school, and I committed suicide.

(1☆3)☆(4）

4. You can replace the corresponding numbers with a and b according to the given rules, and pay attention to the order of operations.

Calculate 1 3 = 1-3 + 1 = -1

From the resulting -1, (-1) (4) = (-1) -(4) + 1 = 4

Idea: M n is the midpoint of the line segment AC and CB, and its essence is to take half of AC and CB, and the remaining line segment M n = half of the line segment AB. In other words, as many times as M and N appear, take the line segment AB in half as many times.

So the final result is: ab (2 to the power of 2010).

I have it,? I'm too much,? It's really hard, huh?

You can't do it, right? Still have a hard time,? Aren't you a good learner?

I really have too many problems,? How did I type out you called me,? I really won't,?

You teach me.

There will definitely be patience waiting for ......

You can go and buy some textbooks, or Peiyou books.

1) Solution: Let the distance between cities A and B be x kilometers.

2（6x+1500）=（10+8）x+1000+70012x+3000=18x+1700

6x=1300

X 217A: The distance between cities A and B is 217 km.

2) Solution: A: 6s + 1500 + 300 (s 60 + 4) = 11s + 2700 B:

8s+1000+300(s 50+2)=14s+600C: 10s+700+300(s100+3)=13s+1600 So, when 7001000 s<1350

Therefore, 1000 A and B do the same thing.

Company C: 217 100+3 ; Pay the fee: 217 10 700 Select C.

Sorry, I don't know where your data is.