Math Homework Feedback 09 Xiaosheng Initial Paper

Set the circumference x the first encounter, A walks 8, B walks x 2-8, a total of x 2 the second encounter, A walks x 2 + 8, B walks x-8, a total of 3x 2 so: 8 * 3 = x 2 + 8

x = 32 (cm).

Pick D, 40

The number of the most ** roads from A to the point where the circle is located is <> from A to B

Can you be more detailed? Excuse me!

First Question 36 Process 198 Divided by 198 Divided by 44 Second Question Process 198 multiplied by 2 divided by (

The one below the third question is correct, and the fourth question is to multiply the original price by x.

So the answer is 800

2. Average speed 36, average speed of time round trip: 198 2 (

25 = 40 yuan, 40 + 8 = 48 yuan, 1000 48 = 20 and 5/6, enough.

4. Set the original price x, then, x = 800 yuan.

Finally, bin A = bin B = 43 2 = tons.

It turned out that there were tons in bin B.

It turned out that there were tons in the first warehouse.

Answer: It turns out that there are tons in warehouse B, and there are tons in warehouse A.

It can be solved by the equation, let the stock of warehouse A be x, and the stock of warehouse B is y, because y+3=x-3, then y=x-6, and x+y=42, so x+(x-6)=42, the solution of this equation is as follows:

2x-6=42

2x=48x=24

And y+3=x-3, so y+3=24-3 y+3=21 y=21-3 y=18

Then the inventory of warehouse A is 24, and the inventory of warehouse B is 18.

Let the inventory of warehouse A be x and the inventory of warehouse B be y, because y+3=x-3, then y=x-6, and x+y=42, so x+(x-6)=42, the solution of this equation is as follows:

2x-6=42

2x=48x=24

And y+3=x-3, so y+3=24-3 y+3=21 y=21-3 y=18

Then the inventory of warehouse A is 24, and the inventory of warehouse B is 18.

1. This is a problem of tolerance, the area of the triangle EBG the area of the triangle EBH (the same height as the bottom), the area of the triangle EBG the area of the triangle BFH area The area of the square 2 10 10 2 50 square centimeters.

Because the area of the quadrilateral ABCD 6 square centimeters is the overlapping part, the area of the shaded part is 50 6 44 square centimeters.

2. Let the heights of the cylinder and the cone be h, and the equivalence relationship is (2 2 h) (3 3 h 1 3) 3 4.

4h/3h＝3/4

i.e. 4h 3h 3 4 16h 9h

h︰h＝9︰16

The height of the cylinder and the cone are 9 16, respectively.

1.Solution:

Because EBG and EBH are the same high and bottom.

So the area is equal.

Because the square divides the area diagonally.

So the shadow area is 10*10 2=50

2.Cylindrical volume = base area * height.

Cone volume = base area * height 2

Because the base area = the square of r.

So the ratio of the base area is 4:9

Let the cylindrical height be x and the cone height be y

then 3 = 4x4 = 9y 2

then x is three-quarters.

Y is eight out of nine.

Shaded area = s ebg s bfh-sabcd = eb eh 2 fb eh 2-6

eh×（eb fb）÷2-6

44v Cylinder: V Cone = R Cylinder H Cylinder: r Cone H Cone 3=2 H Cylinder: 3 H Cone 3=3:4

H cylindrical: h conical = 9:16

(1) Let the water injection of each inlet pipe for 1 hour be a, and the drainage volume of the drainage pipe for 1 hour is b, if you want to fill the pool in two hours, you need to open x inlet pipes, (4a-b) 5=(3a-b) 15

ax-b)×3=(4a-b)×5②

4a-b=9a-3b, i.e., -5a=-2b a=2 5b, substitute 3(ax-a)=5(4a-a), that is, 3ax=18a, solve: x=6, answer: open at least 6 inlet pipes

2) Solution: 120 3=40 (km), 120+40) 2,160 2,80 (km);

A: The speed of the bus is 80 kilometers per hour

3) Solution: Let the purchase price of each appliance be x yuan, and the price is y yuan from the title y-x=48

6(Solution x=243 y=291.)

Answer: The purchase price of each appliance is 243 yuan, and the price is 291 yuan.

Set the water inlet of the upper pipe per hour is x, the water volume of the lower pipe per hour is y, and the total water storage of the pool is s, and now it is necessary to fill the pool with water within 3 hours, and the water inlet pipe should be opened z.

Title: 5 (4 x y) s (1).

15（2x－y）＝s （2）

3（zx－y）＝s （3）

Obtained by equation (1).

y＝4x－s／5

Substituting equation (2) obtains:

15（2x－（4x－s／5））＝s

x＝s／15

Substituting (3) solution z 6

Therefore, it is necessary to fill the pool with water within 3 hours, and at least 6 inlet pipes must be opened.

Two encounters between the two cars and a total of 4 whole journeys, the first encounter passenger car traveled the whole journey plus the distance between B and C. The second time I met, the truck traveled the whole distance between B and C, and said that the speed of the bus was twice that of the truck, so.

120*2) 2=120 van speed and.

120 (1+1 2)=80 km.

Or: The first encounter, two cars combined two A and B two distances.

Therefore, the speed of the two cars meets for the second time with the speed of = 120 2 2 = 120 kilometers per hour, and the two cars travel 2 distances between A and B.

The first encounter truck traveled the distance between A and C, and the second encounter truck traveled 2 distances between B and C, so the distance between the trucks remained unchanged from time to time, and the distance between trucks remained unchanged, then it can be known that the distance between A and C = 2 distances between B and C.

Therefore, the distance between B and C is 120 (2+1) = 40 km, because when they meet for the first time, the bus travels the sum of the distance between the two places A and B and the distance between B and C, so the speed of the bus is (120 + 40) 2 = 80 km Hour A; Then the speed of the bus is 80 kilometers per hour.

First of all, the set price is $x.

Then, from the meaning of the question, it can be seen that 6 (90% x) = 9 (x-30) solution: x=75

Because the purchase price = pricing - profit.

So the purchase price = 75-48 = 27 (yuan).