In recent years, there has been a great development in the construction of expressways, which has ef

Number of days: A = x B = y, then A completes 1 x every day, and B completes 1 y1 x + 1 y) every day) * 24 = 1

1/x*20+1/y*40=1

x=30y=120

Cost: A per day = x B per day = y

x*24+y*24=120

x*20+y*4o=110

x = multiply by the number of days above.

Hope, o(oThank you.

1) If A is completed in x days alone, then the efficiency of A is 1 x;

The efficiency of B is 1 24-1 x

20*1/x+40*(1/24-1/x)=120*24+40*（x-24）=24x

x=30 test: x=30 is the solution of the fractional equation.

The number of days for A to complete alone is 30 days;

The number of days B completed alone is 1 (1 24-1 30)=120 days.

2) If A completes the collection of y million yuan alone, then the work for 24 days will receive y*24 300,000 yuan.

B works for 24 days and receives (120-y*24 30) yuan, and (120-y*24 30)*120 240,000 yuan is collected alone.

20/30*y+40/120*（120- y*24/30）*120/24=110

y=135 test: y=135 is the solution of the fractional equation.

A alone completed the collection of 1.35 million yuan;

B completed the collection of 600,000 yuan alone.

Summary. Hello dear, the answer is as follows: A needs 1.35 million yuan to complete it alone, and B needs 600,000 yuan to complete it alone.

Application question: In recent years, the construction of China's expressway has developed greatly, promoting China's economic construction, a highway under construction to bid, the existing A and B two engineering teams, team A alone can be completed in 30 days, team B alone can be completed in 120 days; If the two engineering teams A and B cooperate, the cost is 1.2 million yuan; If A does Sun Lutang alone for 20 days, the rest of the project will be done by B, which will cost 1.1 million yuan. Q: How much does it cost for the two teams A and B to complete the project alone?

Hello dear, the answer is as follows: A needs 1.35 million yuan to complete it alone, and B needs 600,000 yuan to complete it alone.

The process of solving the problem is as follows: if A completes the collapse alone, it will cost X million yuan, and B will need Y Yuan to complete it alone, then it will take 1 (1 30 + 1 120) = 24 days (x 30 20 + y 120 40) = 110 (x 30 + y 120) 24 = 120 to solve x = 1.35 million yuan and Y = 600,000 yuan.

Our country attaches great importance to the construction of highways, as of this yearThe total mileage of expressways built in China has reached 160,000 kilometersThis also enables China to have the world's largest highway network, which reflects the strength of China's comprehensive national strength, which also makes our people very proud.

As one of the products of economic development, it is necessary to build expressways, which can not only integrate the markets in all regions of the country, but also enable the circulation of human resources and resources in various regions, so as to help the coordinated and cooperative development of various regions. The construction of expressways not only brings a lot of benefits to various regions, but also brings a lot of convenience to each of us.

1. The traffic safety law stipulates that the minimum speed on the highway shall not be less than 60 kilometers per hour, which also makes the average speed of the highway very high. As a result, we can travel at a faster speed when going to other places, and since there are no traffic lights on the highway, this can also help us reduce travel time, which is also an advantage that ordinary roads do not have.

2. Compared with ordinary highways, highways have more and wider lanes, so the transportation volume of expressways will be larger, which also helps us to transport goods across regions more conveniently.

3. Safer highways pay great attention to quality assurance during construction, compared with ordinary highways, not only the road surface is more solid and flat, but also the ramp is relatively gentle, which also allows us to get a safer guarantee when driving.

In addition to the above, there are many benefits to building highways, such as promoting the development of automobile manufacturing, making cars bigger and faster, which also allows us to buy better vehicles. In addition, the construction of expressways will promote the economic development of the areas along the route, thereby making it more convenient for the residents of the area.

All in all, the benefits of building highways are many, and only by continuing to strengthen the construction of infrastructure such as highways can our country develop faster and faster, and people's lives will be better and better.

The express delivery industry is more time-sensitive, and the products in some places are also sold to various places, and it is more convenient for people in other places to go home, too much, thanks to the development of the motherland.

1.Convenient transportation, fast passage, refusal of congestion. 2.Closed operation, high degree of safety, reduce the occurrence of car accidents. 3.Saving oil is conducive to environmental protection. 4.Save time and speed up productivity.

It brings a lot of convenience, it will be particularly convenient in travel, and it can also reduce the time in the process of driving, and the road surface is also very stable during driving.

It is easy to travel between the two regions, which also reduces the transportation time and increases the speed of the process.

a = the amount of frontal clusters on day A B = the amount of work on day B.

a+b)*24=20a+40b

24a+24b=20a+40b

4a=16b

a=4ba+b)*24=5b*24=120b: number of days required by B = 120b b=120 number of days required by A=120b 4b=30

A = the first day of the first day of the first day of the first day of the first day of the first day of the first

a+b)*24=120 a=5-b

20a+40b=110 100-20b+40b=110 b= a=total cost of B = cost of A=

It takes a day to complete the armor alone

20 A + (1 24 -1 A) 40=1, the solution is a=30, and the test a=30 is the solution of the original equation;

The number of days for B to complete alone is 1 (1 24 -1 a) = 120 Answer: A completes 30 days of study alone, and B needs 120 days to complete alone;

If A's daily cost is b0,000 yuan, then B's cost is 120 24-b = (5-b) million yuan

20b+40 (5-b)=110, the solution is b=, 5-b=

10,000 yuan, 10,00

Answer: The cost of A to complete this project alone is 1.35 million yuan, and the cost of B to complete this project alone is 600,000 yuan

A = A day of engineering B = B day of engineering.

a+b)*24=20a+40b

24a+24b=20a+40b

4a=16b

a=4ba+b)*24=5b*24=120b: number of days required by B = 120b b=120 number of days required by A=120b 4b=30

A = Fee for Day A B = Fee for Day B.

a+b)*24=120 a=5-b

20a+40b=110 100-20b+40b=110 b= a=

The total cost of B = the cost of A =

Solution: Set up two teams A and B to complete the project separately, each requires x and y million yuan respectively, and the cooperation of two teams A and B takes T days.

t 30 + t 120 = 1 to get t = 24, from the known conditions can be listed as a binary equation as follows: xx24 30 + yx24 120 = 120, xx20 30 + yx (1-20 30) = 110, the solution x = 1.35 million, y = 600,000.

(1) How many days does it take for teams A and B to complete the project separately?

Set up A and B to complete the project separately It takes A day, and Day B regards this project as 1

Then the amount of work done by A and B every day is 1 a, 1 b

Columnable Equations:

1/(1/a+1/b)=24

20/a+40/b=1

Solving this system of equations yields: a=30, b=120

Therefore: It takes 30 days and 120 days for teams A and B to complete this project separately (2) How much does it cost for teams A and B to complete this project separately?

Set up A and B to do this project separately and need to spend $0,000 per day respectively, and Y million yuan can be listed according to the meaning of the equation

24x+24y=120

20x+40y=110

The solution can be obtained: x=, y=

Therefore, team A needs a total cost of 300,000 yuan to complete this project alone, and team B needs a total cost of 1.2 million yuan to complete this project alone.

Therefore, teams A and B need to spend 1.35 million yuan and 600,000 yuan per day respectively to do this project alone.