Ask for 3 6th grade math application questions! If you can, please tell us what each equation is loo

Question 1. Solution: If the total weight of this alloy is x grams, then the weight of gold is x 2 + 15 grams, and the weight of copper is x 3 + 5 grams.

The sum of the weight of gold and copper is the total weight of the alloy.

i.e. x 2 + 15 + x 3 + 5 = x

x=24A: The total weight of this alloy is 24 grams.

Question 2. Solution: If the second building costs x 10,000 yuan, then the first one costs 3x-320,000 yuan, and the total cost of the two houses is 7x 30,000 yuan.

i.e. x+3x-32=7x3

x = A: The second cost engineer 10,000 yuan.

Question 3. Solution: Let A and B be separated by x kilometers, and the time taken by B to the whole journey to 5 8 hours is 5 x 8 (x 10) = 25 4 hours, and the travel time of the two cars is the same, 25 4 = (1-1 6) x 80

x = A: A and B are kilometers apart.

1——— set the weight of this alloy x grams. 1 2x+15+1 3x+5=x, so 1 6x=20, so x=120

2——— total cost of x 10,000 yuan, 3 7x * 3-32 = 4 7x, so 5 7x = 32, so x = so the second house = 3 7*

3——— Because B lines 1 10 per hour, the time is (5 8) (1 10) * 80 (5 6) = 600

1) x 2 +15 + x 3 + 5 =x to get x=1202) 3 7 * 3x - 32 + x) = x to get x=3) Let the full length be x, then when line B reaches 5 8 of the whole journey, it takes (5 8) (1 10)=25 4 hours.

80 * 25 4) +x 6 =x gives x=600

1 Plan 25%.

2 has x 1 4x + 35 = 2 3x solution x = 843 30 * 21 * yuan.

4 is set to xx=3800

or x=3818 exclusion.

So x=3800

The actual completion of the plan is to regard the output of the plan as unit one, and the actual excess of the plan is (25)%.

2. There is a batch of welding rods, three-quarters of which was used last week, and 35 tons were shipped this week, and the welding rods are equivalent to two-thirds of the original. How many tons of original welding rods? （1-3/4)x+35=2/3x x=84

3. The park only sells two kinds of tickets: 5 yuan for each individual, 30 yuan for each group ticket for 10 people, and 10% discount for buying more than 10 group tickets, 208 people visit the park today, how much is the minimum amount to pay? 200/10=20 20*30*

4. The state stipulates that individuals who publish articles and publish books are calculated as follows: 1. No tax shall be paid if the manuscript fee is not higher than 800 yuan; 2. The manuscript fee is 800-4000, and the 14% tax is paid for the part exceeding 800 yuan; 3. If the manuscript fee is higher than 4,000 yuan, 11% of the total manuscript fee shall be paid. Mr. Wu has to pay a manuscript fee and pay personal income tax of 420 yuan according to law

How much is Mr. Wu's manuscript fee? 420/

1. Planning;

2. (Equations have already been learned in the sixth grade).

Set: The weight of the original electrode is x

1-3 4) x + 35) x = 2 3 x = 84 (tons).

Another: Three-quarters were used, that is, the remaining quarters, plus 35 for the original two-thirds, that is, 35 thought of the original (two-thirds - one-quarter) that is, five-twelve, each divided into 7, the original total was 7*12=84 (tons).

3. The first 200 must be sold for group tickets with 20 * 30 = 600 (yuan) 8 people to buy individual tickets for 40 yuan, and only 30 yuan to buy group tickets.

So buy 21 group tickets 21 * 30 = 630 yuan.

Counting the discount, it is 630* yuan.

4. No tax is required for manuscript fees below 800.

800 - 4000 to pay 0 3200* tax higher than 4000 to pay more than 4000 * tax to pay 800 - 4000 yuan to pay the manuscript fee between 800 - 4000.

Manuscript fee = 420 + 800 = 3800 RMB.

1.(1) Actual production (2) 140

2.Set: original x tons 3 4x+35=2 3x 3 4x-2 3x=35 1 12x=35 x=420 tons.

3.Buy 21 group tickets and get 21*30*4(x-800)*14%=420

x=420/14%+800

x=3800 yuan Answer: Mr. Wu's manuscript fee is 3800 yuan.

1. Planning;

2. Let the original x tons, x 4 + 35 = 2x 3, x multiplied by 30 + 18 times 5 times * 14% = 448

420 divided by 14% = 3000

1. Finally: A 270 * 5 (4 + 5) = 150 B 270 * 4 (4 + 5) = 120 copies.

Original: A150 (1-1 6) = 180 copies.

B 270-180 = 90 copies.

2. Front: above = 7:3 to get the front area = 7 * 50 3 = 350 3 square centimeters above:

Left = 3:2 to obtain left surface area = 50 * 2 3 = 100 3 square centimeters of cuboid surface area = 2 * (50 + 350 3 + 100 3) = 400 square centimeters.

Because 12-5=7, the single digit of the subtraction is 5, the subtraction is actually 35 and is regarded as 55, and 55 27=82 is considered to be 82 by the subtraction, and the actual is 87, so the correct equation is 87-35=52

1. where represents the square index 2

Bottom diameter: 80 2 10 = 4 (cm).

Cylindrical volume: cubic centimeters).

2. Diameter: cm).

The area of the exposed surface (one face, is a triangle): 6 * 6 2 = 18 (square centimeters) The sum of the surface area increases the surface area of the cone (2 sides): 18 * 2 = 36 (square centimeters) 3, the radius of the bottom surface: m).

Cone volume: (1 3) * (cubic meters).

How high is the pile: m).

1.After cutting, two new square areas are added, each area is 40, and the height of 10 is 4cm, and the diameter of the bottom of the cylinder is 4cm, and the volume of the cylinder: you should know the diameter of the bottom surface.

2.After cutting, the surface area is increased by two triangles with a height of 6cm compared with the original, the bottom edge of the triangle is the diameter of the circle on the bottom surface of the cone, and the length of the bottom edge of the triangle can be obtained according to the circumference of the bottom surface, and then the area of the triangle is obtained, multiplied by 2 to obtain the area of the increased part.

3.Calculate the volume of the cone, divide by the base area of the box, and the result is that the formula for how high can be stacked has been forgotten, and the answer is referred to above.

If you don't remember the formula, ignore the above paragraph.

Question 1: The radius of the original cylinder r=80 2 10 2=2cm, volume = r2 h=40

Question 2: Bottom surface diameter =

The surface area has increased s=(6 6 2) 2=36cm2Question 3: Radius of the wheat stack=

Pile volume = (

Height h=1st floor The first question is miscalculated.

1. The surface area is increased by two rectangles, so according to the title:

Bottom radius: r=(80 2) 10 2=2(cm) volume: v=s*h= r*r*h

v cubic centimeter) Answer: . . .

2. Cut out are two triangles, circumference = 2 r, so r

s cut = 3 * 6 2 = 9 (square centimeter) s increase = 2 * 9 = 18 (square centimeter) Answer: .

3. This question is about volume, according to the meaning of the question:

R bottom S bottom = r * r square meters).

v cone = bottom area * h 3 = cubic meters).

h=v s= A:. . .

Note: Because it is inconvenient to play the symbol, * is multiplied by r, and *r is the square of r.

1.The area of the two rectangles is increased, each 40 square centimeters, the rectangle is long = 10 high, so the base diameter is 4 centimeters, and the volume is square centimeters.

2.Circumference = pi multiplied by diameter, so the diameter is 6cm, there are two more triangles after cutting, the bottom is 6, the height is 6, the area is 18 square centimeters, and the two are 36, that is, 36 square centimeters more.

3.The volume of the wheat pile remains the same before and after, and the diameter of the cone bottom is 6 meters, so the volume is square meters, I hope it can help you!!

...Such a simple question, but also ask to explain that you did not listen to the class!

One, 10 ==

Answer: It is necessary to tie three cylinders for a week.

II. 100

10 points == m.

Answer: Xiaoli has taken less rice than Xiaofang.

3. Meters 1+ meters.

A: The little girl can go straight up.

1.Master Zhang used iron wire to tie together 3 cylinders with a diameter of 10 cm (excluding joints), how many centimeters does it take to tie 3 cylinders for a week?

10×2.Xiaoli and Xiaofang walked in the opposite direction of the same point on a circular playground with a diameter of 100 meters, Xiaoli walked meters per minute, Xiaofang walked meters per minute, when Xiaoli and Xiaofang met, how many meters less did Xiaoli walk than Xiaofang?

100 points.

m 3A circular hole with a diameter of 1 meter, a little girl with a height of meters can't go straight over, if you increase the circumference of this hole by meters, can the little girl go straight over?

1+ is greater than can be passed upright.

①x=143/(10+1)=143/11=130

If the top angle is x, then x+ degrees get x=45 degrees, and the bottom angle is 45*

Add water after drinking half of it for the first time The amount of milk is 1 2 After drinking half and adding half a glass of water for the second time, the amount of milk is 1 4 So the ratio of milk to water is 1:3