6th Grade Math Available Hypothesis Equation Urgent!!

Set up male x people and female y people.

then x+y=90,70*x(total score for boys)+80*y(total score) = 90*73 (total score).

Set up the x question correctly.

10x (correct score) + (12-x) * (5) (wrong score) = 90 set 10 yuan x sheets, 2 yuan and 5 yuan y sheets.

Then x+2y=50 (the equation for the number of remuneration sheets), 10x(the sum of the 10 faces) + (2+5)y (the sum of the 2 and 5 faces) = 240 (the equation for the remuneration value).

The equation solves itself.

Let's say it's all boys.

70*90=6300 points.

73*90=6570 points.

6570-6300 = 270 points.

80-70 = 10 points.

Woman; 270 10 = 27 people.

Male: 90-27=63.

Let's say it's all right.

12*10=120 points.

120-90 = 30 points.

5 + 10 = 15 points.

False 30 15 = 2 lanes.

Yes 12-2=10 lanes.

Solve 2 yuan x book, 5 yuan x, 10 yuan (50-2x) sheets.

2x+5x+10*（50-2x）=240

7x+500-20x=240

500-13x=240

13x=500-240

13x=360

x=360/13

2 yuan, 5 yuan x=20

10 yuan 50-2 * 20 = 50-40 = 10 sheets are good If you are not satisfied, you can ask, hope.

Male x female y70x+80y=90x73

x+y=70 male63 female27

True x False yx + y = 12

10x-5y=90 x=10 y=2 pairs of 10 questions.

10 yuan x sheets, 2 yuan and 5 yuan are all y sheets.

x+2y=50

2y+5y+10x=240

x=10 y=20 10 10 sheets.

90 people competed, with an average score of 73 points. The average score for boys is 70 and for girls is 80. How many men and women are there?

Boy x person Female student y person.

x+y=90

70x+80y=90×73

x=63y=27

12 questions, 10 points for doing one correctly, and 5 points for deducting 5 points for one wrong, you must not do it. Xiao Ming scored 90 points. How many are right?

Set the x lane right.

10x-5×(12-x)=90

x = 10, remuneration 240 yuan, 2 yuan, 5 yuan, 10 yuan. A total of 50 sheets. 2 yuan is as much as 5 yuan, how many are 10 yuan?

Set 10 yuan x ticket.

10x+(50-x)(2+5)/2=240x=10

1. Let the number of boys be x and the number of girls be y

x+y=90

70x+80y=90*73

Solve the equation to obtain: x=63;y=27

2. If the correct value is x, the wrong number is 12-x

10x-5（12-x）=90

Get x = 103, set 10 yuan for x sheets. Then 2 yuan and 5 yuan are (50-x) 210x+2*(50-x) 2+5*(50-x) 2=240x=10

Let the male x number be male, and because 90 people compete, the female student (90-x) person will have an equation with equal total scores.

70x+80（90-x）=90*73

So x=63

There were 63 boys and 27 girls.

12 questions, 10 points for doing one correctly, and 5 points for deducting 5 points for one wrong, you must not do it. Xiao Ming scored 90 points. How many are right?

Let Xiao Ming do X questions correctly, 12 questions, and wrong (12-x) questions, which are derived from the meaning of the question.

10x-5（12-x）=90

x = 10, remuneration 240 yuan, 2 yuan, 5 yuan, 10 yuan. A total of 50 sheets. 2 yuan is as much as 5 yuan, how many are 10 yuan?

Set 10 yuan x sheets, because there are 50 sheets in total, 2 yuan and 5 yuan are the same as much, then 2 yuan and 5 yuan each (50-x) 2 sheets, by the title.

10x+2*【（50-x）/2】+7*【（50-x）/2】=240x=10

2, assuming that the answer is correct, the calculation is the answer, the wrong is 20 5 This is the case that the assumption is correct, and then use this number -86 is the difference number, and finally use him (5+2), and finally use 20-

Column: 20-(20 5) (5+2).

1.Because the number of 2 and 5 is the same, so the two denominations add up to a multiple of 7, because there is a total of 240 yuan, so 2 and 5 must add up to 70, 140 or 210, and the number of 2 and 5 is 40, so there are 10 denominations of 10 yuan.

2.2 points will be deducted for 1 wrong question, and a total of 86 points will be scored, so you can only deduct 4 points, 14 points, or 24 points... Substitution solution is 2 wrong to 18.

These three questions can be seen as chickens and rabbits in the same cage.

1.Assuming that all are 10 yuan coins, there are 10x50 500 yuan, a difference of 500-240 260 yuan, and a 2 yuan coin and a 5 yuan coin are 10-2 + 10-5 13 yuan, then 2 yuan and 5 yuan coins each have 260

13 20 sheets, 10 yuan coins have 50-20-20 10 sheets.

2.The difference between correct and incorrect answers is 5+2 7 points, assuming that all the answers are correct, then there are 20x5=100 points, a total difference of 100-86 14 points, then the wrong answer is 14

7 2 questions, 20-2 18 questions answered correctly.

3.The difference between intact 1 box and damaged 1 box is 5 + 40 45 yuan. Assuming that all are intact, you should get 2000x5 10000 yuan, a difference of 10000-9190 810 yuan, then a total of 810 is damaged

45 18 boxes.

1. Set the face value of 2 yuan x sheets.

$5 x of the face value

The face value of 10 yuan is 50-2x.

So 2x+5x+10(50—2x)=240 solves x=20

Therefore, the face value of 10 yuan has 50-2x=50-20*2=10 sheets, and 2 sets Zhang Ming to answer x questions correctly.

then answer 20-x questions incorrectly.

So 5x—2(20—x)=86

Solve x=18

So Zhang Ming answered 18 questions correctly.

3.During transportation, a total of X boxes of glass were damaged.

then intact is 2000-x

So 5 (2000 - x) - 40 x = 9190

Solve x=162

As a result, a total of 162 boxes of glass were damaged during transportation.

Car B is 80 100 80 times the speed of car A, when car A has traveled 50, car B has traveled 50 * 80 40 from place B, and the difference is 1 40 60 of the whole journey

This 60 is 54 kilometers.

The distance is 54 60 90 km.

When car A arrives at place B, car B has traveled 80% of the whole journey, and it can be seen that the speed of car B is 80% of car A;

Therefore, when car A has traveled 50% of the whole journey, car B has traveled 40% of the whole journey, and car B is still 54 kilometers away from place B, and this 54 kilometers is 60% of the whole journey, so the whole journey between car A and car B is 54 60% = 90 kilometers.

When car A reaches 50%, car B is still 54 kilometers away from place B, and when car A reaches place B, car B travels 80% of the whole journey. It shows that car A is still at 40% when car B reaches 50%, 40% = 54, and this (40%=54) is regarded as 1, so 100% = multiplied by 40 = 100 is the whole process.

Let this rope be x meters long.

The length of the first cut is (20%x+3) meters.

The length of the second cut is (1 3x-2) meters.

There are 6 meters left. From the equation x-(20%x+3)-(1 3x-2)=6, the solution of x=15 meters is obtained.

This rope is x meters long.

x-(20%x+3)-(1/3*x-2)=6x=15

The rope is 15 meters long.

Assuming that all 29 animals in the cage are chickens, there should be a total of 29x2=58 legs. Now take out 1 chicken and put in a rabbit, there are still 29 in total, but there are 2 more feet. For every rabbit changed, there are 2 more legs.

There are 92 feet in the cage, 34 feet more than 58, so the number of rabbits: (92-29x2) (4-2) = 17

Chicken: 29-17=12

Assuming that the 29 in the cage are all chickens, then there are a total of 58 legs, and there are 34 extra legs, and these 34 legs are two more legs than the chickens, so we can know that there are a total of 17 rabbits and 12 chickens.

Question 1: Chickens and rabbits have only one head, which is a total of 29. Suppose that all the chickens and rabbits have two legs (58 legs) folded, then only the rabbits are left standing on two feet (92-58=34), then it is conceivable that there are 17 rabbits and 12 chickens!

Take the first question as an example, 29 heads, 92 feet.

Suppose you drink behind the scenes and send a toolbox to go then.

Let's say one big box is equal to 2 small boxes, then you can think of 12 small boxes, so you want to have 20 balls in a small box, and 40 in a large box.

Equation x in a small box and 2x in a large box.

4x+4x2x=240

Solution x=20

2x=40

Each large box contains 40 table tennis balls, and each small box contains 20 table tennis balls.

These three questions can be seen as chickens and rabbits in the same cage. 1.Assuming that all are 10 yuan coins, then there are 10x50 500 yuan, a difference of 500-240 260 yuan, a 2 yuan coin and a 5 yuan coin are 10-2+10-5 13 yuan, then 2 yuan and 5 yuan coins each have 260 13 20 sheets, and 10 yuan coins have 50-20-20 10 sheets.

2.The difference between correct and incorrect answers is 5+2 7 points, assuming that all the answers are correct, then there are 20x5=100 points, a total difference of 100-86 14 points, then 14 7 2 questions are answered incorrectly, and 20-2 18 questions are answered correctly. 3.

The difference between intact 1 box and damaged 1 box is 5 + 40 45 yuan. Assuming that all of them are intact, they should get 2000x5 10000 yuan, a difference of 10000-9190 810 yuan, then a total of 810 45 18 boxes are damaged.

The ratio of height to bottom diameter is 3 to 1

The ratio of height to bottom radius is 6 to 1

Let the radius be r and the height be 6r

v=r*r*r=8

r=2a=2r=2*2=4cm

h=6r=6*2=12cm

s surface area = 4 * 12 * 4 + 4 * 4 * 2 = 192 + 32 = 224 cm2

The cylindrical surface area is the surface area of the cuboid.

If the radius of the bottom surface is x cm, the height is 6x cm

Cylinder volume: ·x 2·6x=

x=2, that is, the bottom side of the cuboid is 2 2=4cm

The height is 2 6 = 12cm

It turns out that the surface area of the box is.

2 (4 4+2 4 12)=224 cm 2 (The volume in the title seems to be!) )

Let the bottom diameter d=2r and the height be 6r

v=πr²·6r=

r=2（cm）

Surface area = 2 (2r) + 4·2r · 6r = 56r = 56 * 2 = 224 (cm).

Let the bottom radius be x, then the height is 6x, then x=2, the bottom diameter is 4, and the height is 12

The surface area of the box is diameter (base length) * diameter * 2 (both sides) + 4 (4 sides) * 12 (height, also long) * 4 (width, also base length).

Multiply 12 on both sides of the equation and you're fine.

3x+6x=1

Equal to 9x=1