Inequalities, inequalities and answers

Some people go on a tour When a room is allocated 4 people, 3 people have no place to live in a room, 8 people have a room left, and a room is not empty and not satisfied, ask how many people, how many rooms?

There is room m, and when there are 8 people, there is a room empty and one is dissatisfied, so 0<4m+3-8(m-2)<8

0<19-4m<8

11 4 so m = 3 or 4, corresponding to 15 or 19 people

Set x people for 4x + 28 milk.

So 1<=(4x+28)-5(x-1)<41<=-2x+33<4

32<=-2x<-29

So at least 15 people.

If the number of people is x, there are:

1≤(4x+28)-5(x-1)＜4

1≤33-x＜4;

29＜x≤32;

At least 30 elderly people;

Good luck with your studies.

Hello! [It has been certified by a famous teacher, absolutely correct].

There are at least 30 elderly people in nursing homes

Set: 45-seater passenger car (A) x cars. 60-seater passenger car (B) 1, A x car, then B is x-1 car.

then 45x = (x-1)60-30

x=6 is 45*6=270 people.

2. A rents x cars, and B rents x+1 cars.

Then 45x+60(x+1)=270 (the number of people on the spring outing is the same as the first question) x=2 to know that A has 2 cars and B has 3 cars.

The rent is 570*2+630*3=3030

Solution: (Song 1) Set: Buy ax only buy a = buy b a = b = xx + 20 = 2x-10

Solution x=30

Therefore, there is a total shortage of finches to buy 30 breeding rabbits in the early part of the cherry blossoms.

2) Set: Sell ax only Sell b (30-x).

15x+16（30-x）≥280

Get x 30-x

The solution results in x 15 x 200 x 15 x being positive integers.

There are x=0 x=1 x=2 x=3 x=4 x=5 x=6 x=7 x=8 x=9 x=10 x=11

x = 12 x = 13 x = 14 15 schemes.

Is your question wrong?,There are 5 kinds of solutions to the questions you usually do) Set:Profit is w:

w= 15x+16（30-x）

The solution shows that w=480-x x is a positive integer, the smaller the x, the greater the profit w, and when x=0, w is maximum;

The maximum profit is w=16(30-0) w=480

Solution: (1) Suppose: buy ax only buy a = buy b a = b = xx + 20 = 2x-10

Solution x=30

So buy a total of 30 breeding rabbits.

2) Set: Sell ax only Sell b (30-x).

15x+16(30-x) 280

Get x 30-x

The solution is x 15 x 200 x 15 x is a positive and cautious integer.

There are x=0 x=1 x=2 x=3 x=4 x=5 x=6 x=7 x=8 x=9 x=10 x=11

x = 12 x = 13 x = 14 15 schemes.

1.15x0=0 30x16=480 Profit480214x15=210 16x16=256 210+256=466

Answer: 15 schemes: When x=14, the maximum profit is 466 yuan.

The first question: 10+ The number of Qin Liang of the original B rabbit bridge is too wide.

The second question: Set up x A rabbits, Y B rabbits.

x+y=30 15x+16y>=280 x>=20 y<=10

The first big question is a+20=2b-10, a=b, and a=b=30

The second question is that there is a problem with the topic, even if all the A breed rabbits are sold, there are 450 out of 30, and it will definitely not be less than 280.

The starting price of a taxi in a city is 10 yuan (that is, the driving distance within 5 km needs to pay 10 yuan), after reaching or exceeding 5 km, the fare is increased for each additional 1 km (the part less than 1 km is calculated as 1 km), and now someone takes this kind of taxi from A to B, pays the fare, what is the distance from A to B?

Solution: The distance from A to B is about x km, and according to the title, 16 10 and 10 x 11 are obtained

That is, the distance from A to B is greater than 10 km and less than or equal to 11 km

We can set sales** to x

The profit is w=100000 (x-40)(x-40)*x-50x, when x>40.

100000 (x-40)(x-40)*x monotonically decreasing.

50x is also monotonically decreasing.

then x=50.

Most profitable. It should be set at $50 per piece.

Question 1:

Negative quarter x +1 0

Negative quarter x -1

Quarter x 1

x 4 non-negative integer solutions have 0,1,2,3

Question 2: 2x-5 is greater than one-half (2-x).

2*（2x-5）＞2-x

4x-10＞2-x

5x＞12x＞

Question 1:

1 shift: -1 4 times x>-1

1 4 Shift: x<4

The non-negative solutions are: 1, 2, 3

Question 2: Remove parentheses: 2x-5>1-1 2 times x

Also shifted: 5 2 times x>6

x>12/5

Set: If there are x ships, there are a total of (6x+18) people.

0＜（6x+18）-10（x-1）＜10

The solution is to guess the positive integer of the rock.

x = 5, 66x + 18 = 48 or 54

A: There are 48 or 54 employees who participate in the rowing.

Answer: 48 people.

Suppose there are x ships and y people in Brotherbucha, then 6x+18=y, 0