Math Problems, Equation Solving, Math Solving Equation Problems

Solution: Set Zhang Qiang's original x cards, and Liu Wei has Y cards.

x-7/1x+2/1y=945 ①

y-2 1y+7 1x-2 1y+7 1x=220 solution. x=770

y=570 A: Zhang Qiang originally had 770 cards, and Liu Wei had 570 cards.

Solution: Let Zhang Qiang be x and Liu Wei be y

6/7*x+1/2*y=945

945*1 7+1 2*(1 7*x+1 2*y)=220. x=1085

y=30 Answer: Zhang Qiang has 1085 and Liu Wei has 30.

Answer] restore the problem.

In the second exchange, Zhang Qiang took out 945 1 7 135 sheets, and in the first exchange, Liu Wei left (220 135) 1 2 170 sheets, indicating that Zhang Qiang's 6 7 and Liu Wei's 1 2 were 945 yuan, and Zhang Qiang's 1 7 and Liu Wei's 1 2 were 170 yuan.

Comparing it, it can be seen that Zhang Qiang's 6 7 1 7 5 7 is 945 170 775 yuan, then Zhang Qiang originally had 775 5 7 1085 yuan, so Liu Wei originally had 945 170 1085 30 yuan.

Set Zhang Qiang x Zhang, Liu Wei Y Zhang.

One: Zhang has 6x 7+y 2, Liu has y 2+x 7, 6x 7+y 2=945

2: Zhang has 6*(6x 7+y 2) 7+(y 2+x 7) 2, Liu has (y 2+x 7) 2+(6x 7+y 2) 7,(y 2+x 7) 2+(6x 7+y 2) 7=220

Simplify, got. x=1085

y=30

Increase in sales n 10 units previously sold **.

10 solution n=25%.

Then sales should increase by 25%.

Let the increase in sales be x

10,000 divided by (2,500 times 80 100)-10,000 2,500 = x

Solve the equation.

1.Xiao Zhang and Xiao Li respectively traveled from west to east from A and B at the same time, Xiao Zhang rode a motorcycle from place A at a speed of 45 kilometers, Xiao Li rode a bicycle from place B at a speed of 15 kilometers, and Xiao Zhang caught up with Xiao Li two hours later. What is the distance between A and B?

Let the distance between A and B be x kilometers, 45 2 = 15 2 + x x = 60, and the distance between A and B is 60 kilometers.

2.Two cars traveled in the opposite direction at the same time from two cities, A and B, which are kilometers apart. Taxis travel 48 kilometers per hour. The car travels 78 kilometers per hour. How many hours later, the two cars are still kilometers apart?

Let the two cars be kilometers apart after x hours, 48x+78x+ x=4, and the two cars will be kilometers apart after 4 hours.

3.The master and apprentice process the same kind of parts, the master processes 120 parts per hour, the apprentice processes 0 parts per hour, the apprentice processes for 2 hours before the master starts to work, how many hours does the master work and the two make the same number of parts?

How is it possible to have 0 per hour?

4.If a school student goes to a spring outing, if there are 65 people per car, there are 15 people who can't get on the bus, if there are more than 5 people in each car, there is exactly 1 extra car, how many cars, how many students go to the spring outing?

There are x cars, 65x+15=(65+5) (x-1) x=17 has 17 cars.

Students: 65 17 + 15 = 1120 students.

1 (45-15)*2=60

2 Disdainful, too simplistic. Children should do their own homework.

Because δ is not a perfectly squared fraction, it should be an irrational number.

Solution: 1. If the orange has x kg, then the pear has 3x kg, and the apple has 6x kg

x+3x+6x=80

10x=80

x=83x=24

6x=48A: Oranges have 8 kg, pears have 24 kg, apples, 48 kg.

2. If there are x geese, then there are (3x+80) chickens and (2x-20) ducks

x+（3x+80）+（2x-20）=21006x=2040

x=3403x+80=1100

2x-20=660

Answer: If there are 340 geese, there are 1100 chickens, and 660 ducks3, and if there are x teachers, then there are (4x-45) boys and (3x+75) girls

4x-45+3x+75=1150

7x=1120

x=1604x-45=595

3x+75=555

A: There are 595 boys and 555 girls in Guangming Primary School.

1. Let oranges be 3x kg for pears and 2 x 3x = 6x kg for apples.

x+3x+6x=80 gives x=8 kg.

That is, oranges have 8 kilograms, pears have 8 * 3 24 kilograms, apples have 24 * 2 48 kilograms.

2. If there are x geese, the chickens will have 3x+80 and the ducks will have 2x-20

x+(3x+80)+(2x-20)=2100 gives x 340

That is, there are 340 geese, 340 * 3 + 80 1100 chickens, and 350 * 2-20 660 ducks.

3. If there are x number of teaching staff, there will be 4x-45 for boys and 3x+75 for girls

4x-45)+(3x+75)=1150 gives x 160

So there are 160*4-45 595 boys and 160*3+75 555 girls.

Let the orange be x

x+3x+6x=80

x = 8 orange 8

Pears 24 apples 48

2.Let the goose be x

3x+80+x+2x-20=2100

x = 340 goose 340

Chicken 1100 Duck 660

3.The number of teaching staff is x

4x-45+3x+75=1150

x = 160 male 595

Female 555

Let the orange weigh xkg, the pear 3xkg, and the apple 6xkg, so x+6x+3x=80 so x=8 are 8 24 48 respectively

Let the number of geese be x: ducks, 2x-20, chickens, 3x+80, so x+2x-20+3x+80=2100, so x=450, respectively, 340, 660, 1100

Number of teaching staff x. Boys 4x-45 Girls 3x+75 So 4x-45 +3x+75=1150 x=160 So boys 595 Girls 555

Let the number of geese be x the number of ducks is 2x-20 and the number of chickens is 3x+803x+80 +2x-20 +x=2100 and the number of geese is 340

The number of ducks is 660

The number of chickens is 1100

Set chicken x duck y goose 2100-x-y

x=3(2100-x-y)+80

y=2(2100-x-y)-20

Polaroid x=1100, y=660, chicken 1100, duck 660, goose 340

(1) Set the weight of the orange x

6x+3x+x=80

2) Set x geese.

3x+80+2x-20+x=2100

3) Number of teaching staff x

4x-45+3x+75=1150

If the orange is x, then the pear is 3x, and the apple is 6x, then x=8, so the apple is 48 kg, the pear is 24 kg, and the orange is 8 kg.

Let the goose be x, the chicken is 3x+80, and the duck is 2x-20, which adds up to 2100, so x=380, chicken is 1220, duck is 740, and goose is 380

Question 3: I don't know what a teacher means, is a teacher a student?

1 If the orange weighs x kg, then the pear is 3x, and the apple is 2 times 3x.

x+3x+6x=80

1) If there are x kg of oranges, then pears have 3x kg, and apples have 6x kg.

According to the title: x+3x+6x=80

2) If the number of geese is x, the number of chickens is (3x+80) and the number of ducks is (2x+20).

According to the title, it is listed as follows: x+(3x+80)+(2x+20)=21003) If the number of teaching staff is x, then the number of male students is (4x-45) and the number of female students is (3x+75).

According to the meaning of the question, it is listed: (4x-45) + (3x+75) = 1150 These are all equations for solving a class of problems, and the method must be grasped.

Don't scare me, this equation? Question 1 48, 24, 8Question 2

1.A factory accepted the processing of a batch of parts, according to the original quota of each day, it is expected to be completed in 30 days. Now, the efficiency of the work has increased by 50%, and as a result, the product was completed 8 days earlier and 24 more pieces were processed.

So, what was the original processing task accepted? What is the original daily processing quota?

Solution: Suppose the original accepted processing task is x pieces. As a result, x 30 pieces are processed per day, and the efficiency is now increased by 50%, which means that the efficiency is now doubled.

Now the efficiency is (x 30)*(1+50%)=x 20, and the equation is established according to the question.

x 20)*(30-8)-24=x solution gives x=240

Therefore, the original daily processing quota is 240 30 = 8 (pieces).

Answer: The original processing task accepted was 240, and the original daily processing quota was 8 pieces.

2.Two cars A and B are traveling in the opposite direction from AB at the same time, and the meeting point of the two cars is 8 kilometers away from the midpoint of AB and AB. It is known that the speed of car A is times the speed of the car, and the distance of AB is obtained.

Solution: Let the velocity of car B be x, then the speed of car A is, and let the time taken to meet is tDepending on the conditions, the equation is established.

Solve x*t=80

Because the distance l=(

So the distance between ab is km).

A: The distance between AB is 176 km.

1. Set the original daily processing quota to be x.

30x+24=(1+50%)x*(30-8)x=8 (pcs).

The original accepted processing task is 30*8=240

2. Let the speed of car A be, the speed of car B be y, and the length of ab is x kilometers x ( x 2 + 8 (1).

x/( (2)

Obtained from (1) and (2).

x = 176 (km).

The answer is hopefully helpful to you

If the original daily processing quota is x, then it is now 30x for the processing task that was originally accepted, and the task that is now completed is. Now there are 24 more pieces than before, and there are 30x+24=

The solution is x=8, and the original daily processing is thought to be 240 pieces.

Let the distance between the two places be 2s, the midpoint is s, A is faster than B, let the speed of B be x, the speed of A is, the time is t, and the distance traveled by A according to the distance formula s=v*t is s+8=

B travels a distance of s-8=x*t

s=882s=176 is the distance between them.

Question 1: Let the interest tax be x, the equation can be obtained: this is the net interest money without deducting the interest tax, because the interest tax is 5%, so the yuan can be obtained, so the yuan is the interest tax, if the interest after tax is asked, that is, the total interest is subtracted from the tax, that is, 2.

97%*20,000*yuan, so the yuan is the after-tax interest, and the money that Dad can get back is divided into two parts, that is, the principal of 20,000 and the after-tax interest, and the two are added to get the total amount of money withdrawn (note, I am in junior high school, I don't know if this question is rounded, if you need to round up, you can directly round off the decimal I found).

The second question: set can take out x yuan, because there is no interest tax on this question, so it is easier to find, that is, 8000 (principal) + 8000 * 3.24%*3 (total interest) = x, find x = yuan, if you need to round it up, it is 8778 yuan.

Question 3: Set the annual interest rate to x, since the deposit is 500 and the yuan is withdrawn, the interval is 2 years, you can get 500 (principal) + (500x) 2 (interest) = total principal and interest), solve x = and turn it into a percentage.

Question 4: If there is x yuan after three years, the equation 5000 (principal) + 3 * interest tax deducted ) = x is obtained, and x = 249 is obtained75 + 5000 = yuan (rounded to your own count).

Question 5: Set the pre-tax salary x yuan, the equation can be obtained: (2380-2000) 95% (the amount of after-tax income over 2000 yuan) + 2000 = x, and the solution is x = 2400 yuan.

These four problems are very simple elementary school math problems, and if you can't do them, you still need to work hard.

1. x = (20000 * (1 + is interest tax).

y=20000*(1+

z=20000*(1 + answer to the first question.)

Some problems can be solved with equations, and some don't use equations at all, and it's troublesome to use equations. . .

Solution: If there are a total of x children, then.

x+8=2x-2

8+2=2x-x

x=10A: There are 10 children in total.