A math puzzle! For me.

Unpack x roosters, y hens, and chicks (100-x-y).

5 x+3y+1/3（100-x-y）=1004y+7x=100

y=25-7x/4

Because x and y are integers.

Then when x=4, y=18 100-x-y=78, when x=8, y=25-14=11 100-x-y=81, when x=12, y=25-21=4 100-x-y=84

Set x roosters, y hens, and z chicks. You get a system of equations:

5x+3y+1/3z=100

x+y+z=100

Let x be known then there is: y=25-x*7 4

z=75+x*3/4

The value of x ranges from 0 to 19

y,z should also be positive integers, then from the above equation we can see that (y=25-x*7 4>=0)x can only take numbers within 14 and are integer multiples of 4.

i.e. x can only take 0,4,8,12

So there are 4 kinds:

1.Buy 0 roosters, 25 hens, and 75 chicks.

2.Buy 4 roosters, 18 hens, and 78 chicks.

3.Buy 8 roosters, 11 hens, and 81 chicks.

4.Buy 12 roosters, 4 hens, and 84 chicks.

Set chick x hen y rooster z

x+y+z=100

5z+3y+1/3x=100

Solve the equation and you're good to go.

A hen is 3 wen a penny, and 3 chicks are a penny, that is, 4 wen can buy 4 chickens, and 100 wen can buy 25 hens and 75 chicks.

Elementary school questions, 100 dollars to buy 100 chickens, there are three sets of solutions, search for yourself"100 dollars to buy 100 chickens"It's easy to find (in fact, I forgot the answer) (*.)

The only way to do this is to exhaustively.

12 Two formulas should be the first question:

The first formula rents the beam and adds the second formula to get: 2x=52, x=26, substitute x=26 into the first bad luck or the second formula gets: y=12

34 Two formulas should be the second question:

The first formula plus the second formula gets: 2x-16=80, x=48, and substitute x=48 into the first or the second formula of the knower: y=32

With the micro-element method. Any small interval [x,dx] on [a,b] is taken, and a small curved trapezoidal shape is obtained accordingly, which rotates around the y-axis to form the body of the body.

The product is: dv=f(x)2 xdx

So the volume of the integrated rotating body is v=2 (a,b)xf(x)dx

Workers produce 4 parts in 5 minutes. At this production efficiency, 8 workers produce parts (8) in 10 hours.

2.A bus stop. There are 5 different routes, each of which departs every few minutes. The first departure is at 6 a.m. and the second departure at the same time at 7 a.m. (30 a.m.).

3.Kindergarten children play games, and each child gets as many balls. In this way, there are 12 balls left, and then 12 balls are added, so each child gets exactly 12 balls, and these children have a total of (12) people, and the original balls (132).

4 = 1, 8 10 60 5 = 960 (pcs).

hour 30 minutes is to find the least common multiple.

3. If it is 12 children, there will be no 12 balls left in the first score, and the children should be 24, and there are 11 24 12 276 balls

According to the title, it is known that the drink that one person gets is.

2+2 3+2 6=18 6=3 bottles.

Then there are 180 3 = 60 people.

Each person planted 1 + 5 2 + 4 3 + 3 5 = 163 30 trees, 60 people planted a total of 60 163 30 = 326 trees.

Those comrades are also correct in using equations, but the calculations are not responsible.

10.Solution: Establish an auxiliary line as shown in the figure, extend the AF intersection DC extension line at the point Q, and obtain gcq age, ahe dhq, abf cqf (f is the midpoint of ab).

AE is the midpoint of AB.

cq：ae=2：1，xg：gy=2:1，s△aeg=ab/2*xy/3*1/2 （ab=1/xy）

s△aeg=1/12

Similarly: dq:ae=2dc:ae=4:1 mh:hn=4:1 s aeh=ab 2*xy 5*1 2=1 20 s hge=1 12-1 20=1 30

Vector method, geometry method, will not ==

It's really hard, no, it's high school.

Ha, I think plane geometry is much better than solid geometry.

7+8=15

The total number of students in the sixth grade is 30.

Half of the third class is given to the first class, and half is given to the second class, and the first class has 7 2 = 14 copies.

There are 8 2 = 16 copies in the second class.

The third shift is 5 8 for the first shift, and the 3 8 is for the second shift.

There are 15 copies in each of the first and second classes.

5 8-1 2 = 1 8 for the third shift, is: 15-14 = 1 for the third shift: 1 1 8 = 8 for the third shift.

Class 1 original: 14-8 2=10 servings.

The original of the second class: 16-8 2=12 copies.

The original ratio of the three classes is:

There are 8x people in the third class, ax people in the first class, and bx people in the second class, by the first condition (ax+4x) (bx+4x)=7 and 8 by the second condition ax+5x=bx+3x

It is solved by the above conditions.

a=10b=12

So the answer is 5:4:6

Suppose there were 8 people in the third class and x people in the first class, then the second class would have [8(x+4)-28] 7

Then x+5=3+[8(x+4)-28] 7x+5=3+8x 7+4 7

x/7=10/7

x=108(x+4)-28] 7=12 people.

Then the original ratio of people is 10:12:8=5:6:4

To the power of 10 is 10

Of course, because a 10th power is 10 (18 5), which can be understood as: first calculate the 18th power of 10, and then open the root number 5 times.

Yes, to the power of 10 or to the power of 10, what is a 10th power.

I haven't studied yet, I should be in the first year of high school, but I have thought about this question, you are talking about the power of 10, right, it is 10, it can be seen as 10 3*10 five-thirds 10, the answer is.