When a project was tendered, two engineering teams A and B received bids for Mathematical Problem 5

It takes X days for A to complete the project alone, then it takes X + 5 days for B to complete the project alone, assuming that the total project is 1, A completes 1 x of the project every day, and B completes 1 (x+5) of the project every day

Then teams A and B cooperate for 4 days to complete project 4*[1 x +1 (x+5)], and the remaining project 1-4*[1 x +1 (x+5)] is completed by B alone, which takes x-4 days, and the equation can be 1-4*[1 x +1 (x+5)]=(x-4)*[1 (x+5)].

Solve the equation to obtain: x = 20 (days).

Plan 1: project amount = 10,000 yuan).

Plan 2: project money = 10,000 yuan), but the construction period is delayed, which is not advisable.

Plan 3: project cost = (10,000 yuan).

Therefore, option three should be adopted.

1) If the construction period is delayed, then option (2) will not be considered.

According to the title, within the specified construction period, B will complete the remaining work in 5 days and A in 4 days.

The ergonomic ratio of A and B is 5:4

To complete all the work alone, the time ratio required by A and B is 4:5, and the specified construction period is: 5 (5-4) 4=20 days.

Scenario 1. The project payment is:

200,000 yuan.

Scenario 3. The project payment is:

10,000 yuan Therefore, without delaying the construction period, option 3 is the most cost-effective.

2) Solution: Set A to be completed in x days, and B to be completed in x + 6 days.

Then: 1-3(1 x+1 x+6)=x-3 x+6x=6 It takes 6 days for A and 12 days for B.

60,000 yuan. $120,000.

30,000 yuan. Scenarios save money.

What's the problem? It is estimated that Hua Luogeng will not be able to do this question when he is alive (reincarnated).

Your question is incredible...

Is it for us to guess your next question?

For one day of construction, it is necessary to pay 10,000 yuan for the project of the A engineering team and 10,000 yuan for the B engineering team The project leading group calculates according to the bidding documents of the first and second teams, and has the following plans: or fierce.

1) Team A completed the project on its own, just as scheduled;

2) It took Team B 6 days longer than the prescribed date to complete the project alone;

3) If the two teams A and B work together for 3 days, the rest of the work will be completed by Team B alone

Let's ask: On the premise of not delaying the construction period, which construction plan do you think is the most economical for the project? Please explain why

Let me teach you, first of all, let the specified number of days be x, then A's work efficiency is 1 x, and B's work efficiency is 1 (x+6), so that 3[1 x+(1 x+6)]+1 (x+6) (x-3)=1, and the solution is x=6.

1) A needs 60,000 yuan to work for six days).

2) According to the title, the requirement is that if the construction period is not delayed, B will take 6 days longer than the specified date, so there is no need to calculate.

3) 30,000 yuan.

From the above, the third option is the most economical bridge project.

Set the deadline to be completed in x days.

Then the efficiency of B is 1 (x+6) and the efficiency of A is 1 x3 [1 (x+6)+ 1 x] +x-3) (x+6)=13 (x+6) +3 x +(x-3) (x+6)=1, and both sides are multiplied by x(x+6).

3x+3(x+6)+x(x-3)=x(x+6)3x+3x+18+x^2-3x=x^2+6x3x=18

x = 6 A to complete the required project alone.

B will delay the construction period if it is completed alone, so it is not considered.

The amount required for the work in the third method.

Therefore, on the premise of not delaying the construction period, you think that the third construction plan is the most economical project.

Solution: Let the specified date be x days From the meaning of the question, 3x+xx+6=1 (3 points) The solution is: x=6

Tested: x=6 is the root of the original equation (5 points).

Clearly, option (2) does not meet the requirements;

Scheme (1): 10,000 yuan);

Plan (3): 10,000 yuan).

Because, on the premise of not delaying the construction period, choose the third construction plan to save the project money (8 points).

Solution: Set the construction period to x days.

From the meaning of the title. 3 3 x-3

x x+6 x+6

Multiply both sides of the equation by x(x+6) to get.

3(x+6)+3x+x(x-3)=x(x+6) The solution yields x=6

It is verified that x=6 is the root of this equation.

Plan 1: 10,000 yuan).

Plan 2: 10,000 yuan).

Plan 3: (10,000 yuan).

Because the construction period cannot be delayed and the plan is the most cost-effective, it is appropriate to choose plan three.

Let team A have a daily efficiency of x, and team B has a daily efficiency of y, and it takes t days to complete the project on schedule from schemes 2 and 3, and y(t+6)=3(x+y)+y(t-3) to get x=2y

Substituting schemes 1 and 2 yields xt=y(t+6).

2yt=y（t+6）

t=6: It takes 6 days to complete on schedule.

On the premise of not delaying the construction period, Plan A needs to pay 10,000 yuan for the project.

Plan C needs to pay 10,000 yuan for the project.

Plan C is the most cost-saving project.

Set the specified construction period to x days:

It takes X days for A to complete the project alone, then it takes X + 6 days for B to complete the project alone, and the equation can be 1-4 [1 x +1 (x+6)]=(x-3) [1 (x+6)].

Solve the equation to obtain: x=6

Plan 1: 10,000 yuan).

Option 2: Because it took six more days, this plan was discarded.

Option 3: 3 (10,000 yuan).

That's why option 3 was chosen.

Simple! Scenario 3.

2) Assuming that the construction period is 10 days for Suixiao:

Plan 1: 120,000 yuan will be paid for the project.

Plan 2: It is necessary to pay 80,000 yuan for the project, which does not meet the requirements of the construction period. Exclude!

Option 3: then you need to pay (10,000 yuan.

So: choose option 3

The engineering team here should be here to "bid" rather than "tender".

Select A to complete the project alone.

This is a simple math problem, assuming that the time to complete it is x days, using conditions 1 and 3 can be calculated: x=15 days, then scheme 1: total **: 10,000; Scheme 10,000; Scenario 3: 10,000.

To sum up: the use of scheme 2, the most economical project money, of course, this is considered from the perspective of the first, but the overall still depends on the requirements of the bidding documents, generally for the project duration is the essence of the bidding documents is not allowed to change, the construction period of team B is not satisfied should not be considered. Because the consequences of the delay are not just the value of saving 5,000 yuan, personal opinion.

It will take X days for Team A to complete this project alone.

A completes the project in one day 1 x, B completes the project in one day 1 (x+5), 4 x+x (x+5) = 1

x = 20 delay in the construction period).

30 So on the premise of not delaying the construction period, the third option is the most economical project.

Solution: Set the construction period to x days.

4 4 x-4

x x+5 x+5

x=20 test: When x=20, x(x+5)≠0

x=20 is the solution of the original equation.

Plan 1: project amount = 10,000 yuan).

Plan 2: project money = 10,000 yuan), but the construction period is delayed, which is not advisable.

Plan 3: project cost = (10,000 yuan).

To sum up, option 3 (i.e., cooperation between A and B) should be chosen

Well, that's the format, just copy it.

Scheme (3) is the most cost-saving project!

Answer process: If the construction period is d, the working day of unit A is a, and B is b, then it can be seen from (2) and (3) that (d+5) b=4a+db can be launched: a:

b = 5:4, from the ** ratio:, it can be seen that the cost performance of unit A is 5::

3, B's cost performance is 4, it can be seen that the cost performance of B unit is higher, so it should be used less in the case of meeting the construction period, and it can be seen that scheme (3) is the most economical project!

This kid, how can the project be tendered like this?

A engineering team, in the project bidding, received a bid from the A and B engineering team, every day of construction, need to pay a project team 10,000 yuan, pay B engineering team 10,000 yuan, the project leading group according to the bidding of a and B two teams, there can be three construction plans, (1) A team alone to complete the project just completed as scheduled. (2) Team B completed the project alone by 5 days longer than the specified construction period. (3) If the two teams A and B cooperate for 4 days, the rest of the project will be completed by team B alone.

Which construction solution do you think is the most cost-effective?

Set the specified construction period to x days:

It takes X days for A to complete the project alone, then it takes X + 5 days for B to complete the project alone, assuming that the total project is 1, A completes 1 x of the project every day, and B completes 1 (x+5) of the project every day

Then teams A and B cooperate for 4 days to complete project 4*[1 x +1 (x+5)], and the remaining project 1-4*[1 x +1 (x+5)] is completed by B alone, which takes x-4 days, and the equation can be 1-4*[1 x +1 (x+5)]=(x-4)*[1 (x+5)].

Solve the equation to obtain: x = 20 (days).

Plan 1: project amount = 10,000 yuan).

Plan 2: project money = 10,000 yuan), but the construction period is delayed, which is not advisable.

Plan 3: project cost = (10,000 yuan).

Therefore, option three should be adopted.

In China's garden industry, the online project bidding is not only one company to invest in the landscaping industry, why not assume a few? Isn't it good to go to the bidding website of China's garden to see the bidding information about the garden industry?

If the duration of the project is x days, then it will take x days for Team A to complete it alone, and it will take x +15 days for Team B to complete it alone.

If teams A and B work together for 4 days, the rest of the work is completed by team B alone, that is: A does 4 days, B does x days, the equation can be listed: 4 x+x (x+15) = 1, and the solution is: x = 60 11;

For the construction scheme (1), the project cost to be paid = 90 11 = 8 and 2 110,000 yuan;

The construction plan (2) delays the construction period and is not considered;

For the construction scheme (3), the project cost to be paid = 120,000 yuan;

Therefore, the construction scheme (1) does not delay the construction period and saves the project cost.

Set the specified construction period to x days:

It takes X days for A to complete the project alone, then it takes X + 5 days for B to complete the project alone, assuming that the total project is 1, A completes 1 x of the project every day, and B completes 1 (x+5) of the project every day

Then teams A and B cooperate for 4 days to complete the project 4*[1 x +1 (x+5)], and the remaining project 1-4*[1 x +1 (x+5)] is completed by B alone, which takes x-4 days, and the equation can be 4*[1 x +1 (x+5)]+x-4)*[1 (x+5)]=1

Solve the equation to obtain: x = 20 (days).

Plan 1: project amount = 10,000 yuan).

Plan 2: project money = 10,000 yuan), but the construction period was delayed by 5 days, 5 * 3000 = 15000 (yuan), 10,000 yuan).

Plan 3: project cost = (10,000 yuan).

Therefore, option three should be adopted.

Answer: Set the construction period = the time used by team A is x, then B is x+54 [1 x 1 (x 5)] x 4) x 5) 1 solution x=20 then x+5=20+5=25

2) Calculate the construction cost of the 3 schemes.

Therefore, from the above calculations, it can be seen that the second option is the most cost-saving project.

How many days is the deadline?