There are 100 chickens and rabbits in the cage, and the chickens and rabbit s feet add up to 248. Ho

According to the first sentence, if there are x chickens and y rabbits, then there are x+y=100, chickens have two legs, and rabbits have four legs, according to the second sentence, there are 2x+4y=248, and 2x+4y=248, then 2(x+2y)=248

That is, x+2y=124, that is, x+y+y=124, where x+y=100, so you can get y=24

Then there is x=100-y=76

x+y=100, multiplied by 2 on both sides, i.e. 2x+2y=200

2x+4y=248

Subtracting the left and right sides of the above two equations yields: 2y=48

then y=24x=100-24=76

Suppose all rabbits and chickens: (4 100-248) (4-2) = 76 (only).

Rabbit: 100-76 = 24 (only).

A: There are 76 chickens and 24 rabbits

First of all, you have to understand that you are messing around.

Chickens have 2 legs and rabbits have 4 legs.

Calculate the part of the feet of the chicken that has more than the rabbit: 14 * 2 = 28 (only) 100-28 = 72 (manuscript only).

72 6 = 12 (only).

Chickens: 12 + 14 = 26 (only).

A: There are 26 chickens and 12 rabbits.

Suppose the number of rabbits increases: 80 4 = 20, the rabbit's feet will tremble as much as the chicken's feet; At this time, there are 100 chickens and rabbits + 20 = 120.

The feet of a rabbit are 4 2 = 2 times the number of feet of a chicken, and the number of their feet is equal, and the number of chickens is twice the number of rabbits. At this time, the rabbit spike pie: 120 (1+2)=40, 120-40=80 chickens in the cage, rabbit:

40-20=20.

The answer is as follows: chickens have 2 legs and rabbits have 4 legs. A rabbit has two more legs than a chicken.

From the question, it can be seen that there are 100 chickens and rabbits, 248 feet, and there are 248-100=48 feet more than chickens. From this, it can be seen that there is a rabbit: a jujube cover.

48 2 = 24 pcs.

There are 100-24 = 76 chickens.

Chickens have two legs and rabbits have four legs. Then use the hypothetical method to solve the problem. Assuming that all 40 are chickens, then there should be 2 * 12 = 24 (only) feet, but there should be 40 feet, less 40-24 = 16 (only) feet, the reason for this difference is that a part of the rabbit is counted as chickens, each of which is less than 4-2 = 2 (only) feet, and the undercounted 16 feet are used to remove the difference between rabbits and chickens 2 is equal to 8.

Because the hypothetical is a chicken, the search is a rabbit, and then use 12-8=4 (chickens). There are 8 rabbits and 4 chickens. Do you understand?

Chicken's feet (100-26) 2=37 feet Rabbit 100-37=63 There is a problem with the question.

This kind of problem is actually very simple, telling you an algorithm that is easy to remember.

Let's say chickens and rabbits are very well trained and understand human speech.

You command, the chicken and the rabbit raise one foot together, and the result: 248-100=148. The command is repeated one more time: 148-100=48.

Now the 48 legs with their feet on the ground are all rabbits, because the chicken's feet are all folded. 48 rabbit legs divided by 2 equals 24 rabbits. The last 100-24 = 76 chickens.

It's easy to get 24 rabbits and 76 chickens.

To give you a more alternative answer: assuming that the rabbits all lift their legs, then the chickens and rabbits are standing on two feet, then there are 2*100 for a total of 200 feet, and the remaining 248-200 48 feet are all rabbits, so 48 2 24 is the number of rabbits, and 100-24 76 is the number of chickens.

If there are chickens x and rabbits, then the system of equations can be listed

x+y=100 (1)

2x+4y=248 (2)

From Eq. (1) we get y=100-x

Substitution (2).

Yes: 2x+4*(100-x)=248

2x+400-4x=248

2x=152

x=76 and thus y=100-76=24

That is, there are 76 chickens and 24 rabbits in the cage.

Regarding the problem of chickens and rabbits in the same cage, I have summarized a formula: (foot 2) 2=number of rabbits. Substitution (248 100 2) 2 24, 24 rabbits, 76 chickens (100 24 76).

Twenty-four rabbits and seventy-six chickens.