Some math problems are urgent, and there are some equations that need to be calculated, big brother

1.The height of the cylinder is constant, and its base radius is proportional to its volume.

2.A cylinder and a cone have equal volumes, and their height ratio is 1:30 and the base area ratio is [1:10].

3.If a times 5 = b times 6, then a out of b is part of a part.

4.Divide 5kg of sugar into 8 equal parts, each part of the total quantity, each part of the weight of 1kg, 5kg of the total quantity.

The simplest integer ratio of ton:50kg is:. The ratio is.

6.The height of the cylinder is 5 decimeters, and the section of 2 squares can be obtained by cutting along the diameter of the bottom surface, and the diameter of the bottom surface of this cylinder is decimeters.

7.When a box with length, width and height is cut into two boxes, the sum of the surface areas of the two boxes is the maximum.

8.The bottom circumference of a cone is 6cm in height. When it is cut in half from the apex of the cone along the height, the sum of the surface areas increases by square decimeters from the surface area of the cone.

9.The number A is the reciprocal of the number B, the number B is 30 after being expanded by 10 times, and the number A is [one-third].

Hour = [2 and 5/12] hours (fill in the score).

1.[Unrated] proportion.

3.Divide it. 4.Divide it, divide it, divide it.

5.：.The ratio is.

6.The diameter is decimeters.

8.[Square decimeter.

10.[2 and a quarter].

1.Proportional.

1/6 1/5 5/8

Dm. 9,1/3

10,2 and 1/4

Positive 1 than the root number is 10 sixths of eighths of 500th of 1000 and 200th to 15 dm 208

Third. [2 and a quarter].

1.Calculate the volume of water in b Volume = length, width, height = 10 6 4 = 240 centimeters.

Then calculate the depth of water put into a Height = volume Length Height = 240 8 5 = 6 cm.

2.Because the side is square, the bottom side length = height = 16 cm, and because the bottom surface is a square, the side length of the square = the bottom side length 4=16 4=4 cm.

So length = width = 4 cm.

Volume = length, width, height = 4 4 16 = 256 cubic centimeters 3Set: 6 grains are counted x times, and 5 are left; 8 seeds and 8 seeds counted y times, and the remaining 7 pieces get: 6x+5=8y+7

So 3x-4y=1

When x=3 and y=2 satisfies the above equation and conforms to the topic, and the amount of sugar is the least at this time.

There are at least 23 pieces of sugar.

Question 1: The volume of water in container B 10*6*4=240 poured into A then 240 (8*5)=6

Question 2: Because the height is 16 and the side is square, it means that the sum of the length of the four bottom edges is 16, then the volume is 4*4*16=256

Question 3: It is equivalent to a number, divided by 6 and left for 5, divided by 8 and left for 7.

Let 6x+5=8y+7 6x=8y+2x, where y is an integer; Therefore, x=0 rounding, x=1 rounding, x=2, rounding, x=3, y=2, so the minimum value is 6*3+5=23

The volume of water in a container is 10*6*4=240, the ground of a container is 8*5=40, and the water in a is 240 40=6

2.If the height is 16 and the side is square, the circumference of the bottom square is 16, the side length of the square is 4, and the volume = 16 * 4 * 4 = 256

3.If you add one, the number of 6 and 8 and 8 and 8 are exactly counted, and the least common multiple of 6 and 8 is 24, minus one is 23.

1-- 10x6x4 (8x5)=6 cm2-- length of the cuboid = width 16 4=4 cm , v=4x4x16=256

3-- In other words, it should be: 5 is 6-1, 7 is 8-1 to borrow the saying that xhy doesn't drink-" Then add one, and you will be counted exactly 6 and 6 and 8 and 8, and the least common multiple of 6 and 8 is 24, and 24 is the smallest that can count 6 and 8 at the same time.

But when you count them all, you add "one". So:

The least number is --6x4 -1=8x3 -1 =24-1 =23

The result of the first question is 6 cm, and the equation is 10*6*4 8 5=6

The volume of the second question is 256 cubic centimeters, and the length and width are both 4 centimeters. Length and width are calculated as 16 4 = 4 cm, and volume is 4 * 4 * 16 = 256 cubic centimeters.

The third question is 23 pieces, and the remaining 5 and 7 pieces can also be understood as 1 less and exactly divided, so the number of candies is at least the least common multiple of 6 and 8 24 and then subtract 1, which is 23.

(6*10)*4=(5*8)*x x=6

The side square means that the circumference of the square on the bottom surface is 16, so the width of the cuboid is 4, and the volume is the base area multiplied by the height = 4 * 4 * 16 = 256

The last one is dizzy, look at the master.

*6*4=240 (cubic centimeters).

240 (8*5)=6 (cm).

4 = 4 (cm).

4*4*16=256 (cubic centimeters).

A: The volume is 256 cubic centimeters, and the length and width are both 4 centimeters.

240cm2=240ml 8*5=40cm 240 40=6cm length 4 width 4 volume 4*4*16=2563There are 5 left, 7 left, that is, 6 is less than one, and 8 is 1 less [6,8] = 24 24-1 = 23

10*6*4=240 (cubic centimeters).

240 (8*5)=6 (cm).

The side square means that the circumference of the square on the bottom surface is 16, so the width of the cuboid is 4, and the volume is the base area multiplied by the height = 4 * 4 * 16 = 256

6x+5=8y+7

When y=1, x=5 3

When y=2, x=3 (integer).

The total number brought in was 23

The volume of water in the container is: 10 6 4 = 240 cm3 Find a container water depth: 240 (8 5) = 6 cm2

It can be seen that the circumference of the bottom square is 16cm, then the length and width of the cube are 4cm, and the volume is: 4 4 16=256cm3

3.At least 23 of them.

In the same time, B runs 20 meters, C runs 20 + 20-24 = 16 meters, C speed: B speed = 16:20 = 4:

5. Explain the distance of C: the distance of B: = 4:

5, and B runs the whole distance, so C's distance is 4 5 of the whole journey, and the part that C does not run is 1 5, 24 meters. The whole distance can be calculated: 24 1 5 = 120 meters.

24 1 5 = 120 meters.

2) C's speed: 120 24 = 5 meters.

Because when A runs the whole distance (120 meters), C only runs (120-20-20) = 80 meters, the time A runs 120 meters = the time C runs 80 meters.

80 5 = 16 seconds.

The speed of A: 120 16 = meters.

Solution: (1).Let the race run x meters, and the ratio of the speed of B and C is 20 (40-24), that is, 5 4, and the speed of B and C is 5a and 4a respectively. From the meaning of the title.

x - 20) (5a) = (x - 40) (4a) then x = 120

2）.C runs the entire course in 24 seconds, so C's velocity is 120 24 = 5 (meters and seconds).

When A reaches the finish line, C has 40 meters left, and their velocity ratio is 120 (120 - 40)=

So the velocity of A is 5 * = (m seconds).

(1) Set the total distance to x meters.

Analysis: Because the time is the same, the ratio of the speed is equal to the ratio of the distance (x-20) (x-40)=20 (40-24)x=120

120-40) 5=16 seconds.

Suppose that the speed of A is x, the speed of B is y, and the speed of C is z, then s x=(s-20) y=(s-40) z s y=(s-24) z

Y = (s-20) x s is obtained by y, z = (s-40) x s is substituted into s (s-20) x s = (s-24) (s-40) x s to obtain s = 120 meters.

If it takes 24 seconds to complete the run, then.

The velocity of C is z = s 24 = 120 24 = 5 m s again, z = (s-40) x s

i.e., 5 = (120-40) x 120

Solution x = m seconds.

They must have been running together (hehe, acquiesced).

Let the velocity of A be v1, the velocity of B is v2, the velocity of C is v3, A runs to the finish line time t1, and B runs to the finish point t2

1) v2 t2 v2 t1 20v 3 t2 v3 t1 16.

v2/v3＝5/4

v2 t2 v3 t2 24 brings the above equation in.

v3 t2 96 knows t2 when C is 24 meters away from the end point, so the whole journey is 96 + 24 120 (m) (2) from the question v3 120 24 5 (m s), v3 t1 s 40 80 (m).

t1＝16（s）

v1×t1＝s

Speed v1

Did they start at the same time?

(1) 200 (1-20%) = 250 (yuan) ......Original price (2) (250 + 80) * (1-20%) = 264 (yuan) ......Method 1: 250 + 80-100 = 230 (yuan) ......The second way is 264 230, so the second way is cost-effective.

1）250*（100%-20%）=200

2) All are purchased at a 25% discount, and a total of money is spent: 250*(100%-25%)=

According to the purchase of 200 yuan to send a shopping coupon: since the shoes only need 98 yuan, you can directly use the shopping coupon, so a total of 250 yuan can be spent.

Because 261>250

Therefore, the two ways are finally compared: shopping according to method 2 is more cost-effective, and you can save 11 yuan, and the "*" in the above formula is the meaning of multiplication.

(1) 200 (1-20%) = 250 (yuan) ......

2) The second option is more cost-effective. Because the clothes are 250 yuan, and the 200 yuan is full, you can get a 100 yuan shopping coupon, and the shoes can be used without spending money, and you can use the shopping coupon to offset it, only 250 yuan in total. If it is the first method, 80 * 80% = 64 yuan, plus 200 yuan of clothes is not cost-effective, it needs 264 yuan.

(1) 200/(1-20%)=250

2) Method 1: (250+80) 80%=264Method 2: 250+80-100=230

So the second way is cost-effective.

The so-called "chickens and rabbits in the same cage" problem can be solved by the hypothetical method:

Method 1: Assuming that all 33 are benches, there should be 33 4 = 132 legs, and 132-100 = 32 more. For each bench lost (replaced with tweezers), there is 4-3 = 1 leg less, so the number of benches should be 33-(33 4-100) (4-3) = 1, and the number of tweezers should be (33 4-100) (4-3) = 32.

Method 2: Assuming that all 33 are tweezers, there should be 33 3 = 99 legs, less 100-99 = 1. And for each reduction of a pan (replaced with a bench), there is an extra 4-3 = 1 leg, so the number of pans should be 33-(100-33 3) (4-3) = 32, and the number of benches should be (100-33 3) (4-3) = 1.

This is a problem of chickens and rabbits in the same cage!!

Assuming that all of them are benches, then there should be 4 legs 33 = 132, which means 132 more legs 100 = 32

So there is a tweezer 32 4 3 = 32

So the stool has 33 32 = 1

In the following language is not good (translate it).

The number of benches should be 33-(33 4-100) (4-3) = 1, and the number of tweezers should be (33 4-100) (4-3) = 32.

1. Start making 24 per day, 1 4 7 = 1 28 per day, a total of 24 1 28 = 672.

After the improvement, 3 4 12 = 1 16 per day, and the number of pieces is 672 * 1 16 = 42.

2. If the car travels 1 4 = 1 4 per hour, then the truck travels per hour = 1 4 * (1-20%) = 1 5, then the truck takes 5 hours.

3. Xiaoqing loads 1 1 5 = 5 baskets per hour, Xiao Ming loads 1 1 6 = 6 baskets per hour, then two people load a total of 11 baskets per hour, then two people load 3 baskets A total of time = 3 11 hours.

4. This batch of coal is 45 (30%-25%) = 900 tons, and the amount of B transportation = 45% * 900 = 405 tons.

5. Set rice x kg, then flour 5x kg, x 30 = (5x-225) 75, x rice = 90 kg, 5x flour = 450

6. Let there be x large barrels and (50-x) small barrels, 4x+2*(50-x)=120, x large barrels = 10, and 50-x small barrels = 40