Chickens and rabbits are in the same cage, with a total of 25 heads and 80 legs, and how many chicke

There are x chickens and y rabbits.

then x+y=25

2x+4y=80

x= 10 y=15

Let's say it's all rabbits.

25x4-80)÷（4-2）

10 chickens.

25-10 = 15 rabbits. Hope!

Solution: There are x chickens and y rabbits.

x+y=25

2x+4y=80

Get: x=10

y=15

Analysis If all 25 rabbits are rabbits, there should be a total of 4 25 = 100 feet, which is 100-80 = 20 feet more than the known 80 feet. If you replace a rabbit with a chicken, you need to reduce 4-2=2 feet. So, how many chickens should be replaced in 25 rabbits to make the difference of 20 feet disappear?

Obviously, 20 2 = 10, just replace 10 rabbits with 10 chickens. So, the number of chickens is 10, and the number of rabbits is 25-10=15.

If you are in junior high school, you should use equations to solve this problem, and if you are in elementary school, you should use the hypothetical method.

Analysis: Assuming that all 25 are chickens, there should be a total of 2 25 = 50 legs, which is 80-50 = 30 feet less than the known 80 feet. If you exchange a rabbit for a chicken, you need 4-2 = 2 more feet.

So, how many rabbits should be replaced in 25 chickens to make the difference of 30 feet disappear? Obviously 30 2 = 15, just replace 10 chickens with 15 rabbits. So, the number of rabbits is 15, and the number of chickens is 25-15=10.

This is a typical chicken-rabbit cage problem! Very representative!

Set x chickens and y rabbits.

x+y=25

2x+4y=80

Solution: x=10

y=15

How many rabbits are there?

80-25x2) 2 30 2 15 (only) How many beams are there for chickens? Number of slags.

25-15-10 (only).

A: There are 10 chickens and 15 rabbits.

Chickens have (25*4-80) 2=10 and rabbits have 25-10=15. If it helps, click on the phone in the upper right corner to check the defect and be satisfied, thank you! Defeat and early debate!

Knowing the total number of heads and the total number of feet, ask the chickens and rabbits how many formulas:

Number of rabbits = ( total number of feet number of chickens total number of feet ) (number of rabbit feet number of chicken feet) number of chickens = (number of rabbit feet total number of feet total number of feet) (number of rabbit feet number of chicken feet) method 1: Let all of them be chickens.

The total number of feet will be 2 total heads, the actual number of extra feet = the actual number of feet - the actual number of 2 total heads, the actual number of feet is more, that is, because there are rabbits, for each more rabbit, there will be 2 more feet, and the number of rabbits = how many 2s are the actual extra number of feet

Number of rabbits = half of the actual total number of feet - total number of heads.

Method 2: Assuming that they are all rabbits, the total number of feet will = 4 total heads, and the actual number of feet is less than that of rabbits, because there are chickens, each chicken has 2 feet less than rabbits.

The actual number of feet is less than all rabbits, how many 2s are missing, that is, the number of chickens = 2 total heads - half of the actual total number of feet.

The number of chickens in the equation method = 2 times the total number of heads - half of the total number of legs.

Number of rabbits = half of the total number of feet - total number of heads.

Method 1: Suppose the number of rabbits in it is x

Then the number of chickens is the total number of heads - x

Total number of feet = 4x + 2 (total number of heads - x).

Total number of feet = 2x + 2 total number of heads.

2x = total number of feet - 2 total number of heads.

x = (total number of feet - 2 total number of heads) 2

x = total number of feet 2 - total number of heads.

Method 2 assumes that the number of chickens in it is x

Then the number of rabbits is the total number of heads - x

Total number of feet = 2x + 4 (total number of heads - x).

2x = 4 total number of heads - total number of feet.

x=2 total number of heads - total number of feet 2

The answer to this question. Number of chickens = 2 times the total number of heads - half of the total number of feet = 9

Number of rabbits = total number of heads - number of chickens = total number of heads - (2 times the total number of heads - half of the number of feet) = half of the total number of feet - total number of heads = 11

Answer: Suppose they are all chickens, with 2x20=40 legs and an extra 62-40=22 legs, and then calculate the number of rabbits 22 (4-2)=11 rabbits. Then there are a total of 22 2 = 11 (chickens) and 20-11 = 9 (chickens).

Assuming that the rabbit has two legs, then 20 heads have a total of 40 legs, and 62-40 is 22 legs, then each rabbit has two more legs, and there are 22 = 11 rabbits.

There are 20-11 = 9 chickens.

(50) chickens;

There are (5) rabbits;

50 (only) 5 (only).

If it is a primary school solution, you can assume that 15 heads are all rabbits, then 15 * 4 = 60 legs more 60-48 = 12 legs, because chickens are counted with two more legs, so chickens have 12 2 = 6, and rabbits 15-6 = 9.

If it is a junior high school solution, you can list equations.

Let rabbit x, chicken y, x+y=15, 4x+2y=48

The solution yields x=9 and y=6

Answer: Let's assume that there are rabbits, and you can use to indicate the number of chickens; According to the number of feet of each rabbit multiplied by the number of rabbits + the number of feet of each chicken multiplied by the number of chickens is equal to 120, the number of rabbits is solved; The total number of chickens is subtracted from the number of rabbits to find the number of chickens.

Solution: Suppose there are x rabbits and (55-x) chickens. 4x+(55-x) 2=1202x+110=120x=555-x=55-5=50Answer: There are 50 chickens and 5 rabbits.

Please give a review thanks.

Suppose 20 are all chickens, then there should be 20 2 = 40 feet, and 48 40 = 8 feet, then 8 2 equals 4, then rabbits should be 4, and chickens should be 20 4 = 16.

There are x rabbits to solve.

4x+2*（20-x）=48

4x+40-2x=48

2x=48-40

x=8÷2x=420-4=16

A: There are 4 rabbits.

There are 16 chickens.

Chickens have (25*4-80) 2=10 and rabbits have 25-10=15. If it helps, then click on the top right corner of the phone to be satisfied, thank you!!

Think of it all as chicken feet first.

Rabbit = (54-20x2) 2 = 7.

Chickens = 20-7 = 13.