Find 15 elementary school math binary equation system application problems

In fact, you don't have to engage in the sea of questions tactics, you can get all the questions in the textbook, master it well, it's no problem to score more than 110 points, you should first master the knowledge in the textbook, there are few exam problems, they have all been done, I hope you have a good score. If there is no question of me, I.

Solution: Let win x draw y lose Zheng Ma town z field, x, y, z are all positive integers less than 12, from the meaning of the question, 3x+y=19

x+y+z=12

For the indefinite party to shout rough range, there are multiple groups of solutions).

The solution is x=6, y=1, z=5

Or. x=5,y=4,z=3

Or. x=4,y=7,z=1

w = respectively substitute the model spring into the above solution, can be obtained.

When x=4, y=7, z=1, w max.

1.Solution: If this person holds X shares A and B Y, then it is derived from the title.

solution, we get x=1000, y=1500

2.Solution: Let win x draw y lose z field, x, y, z are all positive integers less than 12, from the meaning of the question, 3x+y=19

x+y+z=12

In order to clear and correct Wang's indefinite equations, there are multiple sets of solutions).

The solution is x=6, y=1, z=5

Or. x=5,y=4,z=3

Or. x=4,y=7,z=1

w = substituting the above answer to the solution, which can be obtained.

When x=4, y=7, z=1, w max.

Plan 1: Produce up to 4t milk tablets, and sell the rest of the fresh milk directly, then its profit is: 4 * 2000 + (9-4) * 500 = 10500 (yuan) Plan 2:

If 1 day of milk tablets is produced, the remaining 8t of yogurt can be produced for more than two days, which does not meet the conditions of exactly 4 days to be completed, therefore.

Not this method.

If the milk flakes are produced, the rest of the yogurt is produced exactly in 4 days, so it is produced in this way.

then the profit is: yuan).

12000-10500=1500 (yuan).

Therefore, every two plans can produce milk tablets per day, and the production of yogurt per day can get an extra profit of 1,500 yuan.

Plan 1: 4 tons of milk tablets are made, and the remaining 5 tons are sold as fresh milk, profit: 4 * 2000 + 5 * 500 = 10500 yuan;

Scheme 2: Set up x days of processing milk tablets, and the equation can be listed: x+3(4-x)=9, you can know x=, so a total of tons of milk tablets, tons of yogurt, profit: yuan, so the second scheme is the most profitable!

I was tired of doing it when I was in junior high school, but I didn't want to play because of the process. Calculate it yourself, little sister, this kind of application problem is too simple, just sort it out yourself.

You don't have to use a binary equation.

Assumptions can also be used.

Hehe, so modest, I'll see!

Well, it's only 1t, right?

1 Use white iron sheet to make canned food boxes, each iron sheet can be made into 25 box bodies, or 40 box bottoms, a box body and two box bottoms are matched into a set of canned food boxes, the existing 36 white iron sheets, how many pieces of box body are used, how many pieces of box bottom can make the box body and the bottom of the box just match?

2 The sum of the ages of the parents is now six times the age of the children; Two years ago, the sum of the age of the parents and the age of the children was 10 times the sum of the ages of the children; The sum of the ages of the parents is three times the age of the children. Q: How many children do you have?

3 A and B set out from A and A at the same time, and A and B met for the first time when A passed the midpoint, and A and B immediately turned around and walked back after arriving at B and A, and as a result, A and B met for the second time at a distance of 100 meters from A, and the distance between A and B was found.

4. The factory is connected by road and railway between the two places, and the factory buys a batch of raw materials of 1,000 yuan per ton from place A and transports them back to the factory, making products of 8,000 yuan per ton and transporting them to place B. It is known that the road freight rate is yuan (tons, kilometers), and the railway freight rate is yuan (tons, kilometers), and the total cost of these two transportation is 15,000 yuan for road freight and 97,200 yuan for railway freight. How much is the sum of the sales price of this batch of products compared to the raw material cost and the transportation cost?

5 Zhang Dong went to the department store and bought two types of envelopes, a total of 30 envelopes, of which the envelope of model A was used for 1 yuan and 5 jiao, and the envelope of model B was used for 1 yuan and 5 jiao, and the envelope of model B was cheaper than the envelope of model A by 2 cents each. What is the unit price of each of the two types of envelopes?

6 It is known that a railway bridge is 1000 meters long, and there is a train passing through the bridge, and it is measured that the train takes 1 minute from the beginning of the bridge to the end of the bridge, and the time for the whole train to be completely on the bridge is 40 seconds, so find the speed of the train and the length of the train?

7 In a basketball and volleyball game, a total of 48 teams and 520 athletes participated, including 10 players from each basketball team and 12 players from each volleyball team.

8. A factory bought a total of 56 tons of materials A and B, and used 9,860 yuan. If material A is 190 yuan per ton and material B is 160 yuan per ton, how many tons of each of the two materials are bought?

There are 3 kinds of 9 kinds of beverage size packaging, 1 medium bottle is cheaper than 2 small bottles 2 jiao, 1 large bottle is 4 jiao more expensive than 1 medium bottle plus 1 small bottle, large, medium and small buy 1 bottle each, it costs 9 yuan and 6 jiao. How much is each of the 3 types of beverages per bottle?

10 Level 1 students go to the cafeteria for a meeting, if every 4 people sit on a bench, 28 people do not have a place to sit, if 6 people sit on a bench, find the number of students in the first level and the number of benches

1 (2012 Xiamen) solves the system of equations: 3x+y=42x-y=1

2 (2012 Qiandongnan Prefecture) solves the system of equations 2x+3y+z=6x-y+2z=-1

x+2y-z=5

3.(2012 Nanjing) solves the system of equations x+3y=-13x-2y=8

4.(2012 Huzhou) solves the system of equations 2x+y=8x-y=1

6.(2012 Guangzhou) solves the system of equations x-y=83x+y=12

7.(2012 Guangdong) solves the system of equations: x-y=4 3x+y=16

8.(2011 Yueyang) solves the system of equations: x+y=3

5x-3(x+y)=1 ②

9.(2011 Yongzhou) solves the system of equations: 4x-3y=112x+y=13

10.(2011 Yichang) solves the system of equations x-y=12x+y=2

11.(2011 Nanchang) solves the system of equations: x-2y=-1x-y=2-2y

12 (2011 Meishan) Solve the equation: 2x+y=1 x-y=2

13.(2011 Huaihua) solves the system of equations: x+3y=85x-3y=4

14.2011 Guilin) solves a system of binary equations: x=3y-538-2x

15.(2011 Baoshan) solves the system of equations x+2y=9-2y=5

16.(2010 Nanjing) solves the system of equations: 2x+y=4x+2y=5

17.(2010 Yeosu) solution equations: 2x-y=3(1)x+y=7(2).

18.(2010 Huaihua) solves the system of equations: x-y=5 3x-y=-1

19.(2010 Guangzhou) solves the system of equations: x+2y=13x-2y=11

20 (2010 North Sea) solves the system of equations 2x+y=5x-y=1

In both cases, a system of binary equations is used, and the system of equations and their processes are listed. Thank you, (1) Solution: (1 year old at birth) x+(x-y)=37 solution can be obtained x=2y-1 solution can be obtained.

The following system of equations, which is a system of binary linear equations, is ( ).

a． 4x+5y=98x-7z=3

b． x-6y=7

x 3+y 5

6 c． x+y=7

xy=6d． 2x-6=7y-4z

3y=6

There are 30 questions here, I don't know if you can use them, these questions are followed by the answers, I hope you read them.

1. Let the male student have x people and the female student have y people according to the question to list the equation to obtain:

x-4）+（y+3）/2=40

2（x-4）+（y+3）/2=68

Solving the system of equations yields x=32, y=21

2. The merchant purchased 6 mobile phones of type B, X part of type A mobile phone, and part Y part of type C mobile phone, and the equation was obtained according to the meaning of the question.

x+6+y=40

1800x+6 600+1200y=60000 Solve the equation to get x=26 y=8

The merchant purchased 7 mobile phones of type B, X mobile phones of type A, and part y of mobile phones of type C, and the equations were obtained according to the inscription.

x+7+y=40

1800x+7 600+1200y=60000 Solve the equation to get x=27 y=6

The merchant purchased 8 mobile phones of type B, X part of type A mobile phone, and part Y part of type C mobile phone, and the equation was obtained according to the question.

x+8+y=40

1800x+8 600+1200y=60000 Solve the equation to get x=28 y=4

Just answer them separately.

x for males and y for females, 2*(x-4)+(y+3) 2=68

x-4)+(y+3)/2=40

x=32，y=21

A is x, B is y, and C is 40-x-y

1800x+600y+1200(40-x-y)=60000 because 6<=y<=8

Simplification x-y = 20

So there are 3 cases 26, 6, 8, 27, 7, 6, 28, 8, 4

14. Set a load of x tons and B load of y tons.

The result is: 2x+3y= and 5x+6y=35

So you can get: 4x+6y=31, and then get x=4, so y=third total weight: 3x+5y=, freight: