Who can do the following math problems? My daughter won't! [Sixth grade] No! Urgent! That's right. Give more rewards! ! I want answers tonight! Come on!

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1. Analysis: Suppose each animal has 4 legs, and 8 animals * * * have 4 × 8 = 32 legs. 32-28 = 4 more legs than before. Because rabbits have four legs, this extra is the number of chicken legs. (If every animal has four legs, then every chicken has two more.) Then, 4 ÷ 2 = 2 is the number of chickens. 8-2 = 6 is the number of rabbits.

The formula is as follows: the number of chickens: (4 × 8-28)÷ 2 = 2.

Number of rabbits: 8-2 = 6

In the same way, we can find out the number of rabbits first. Suppose every animal has two legs. )

Number of rabbits: (28-2 × 8 )÷ 2 = 6.

Number of chickens: 8-6 = 2

2. The method is as above 1: (4 × 16-46)÷ 2 = 9.

Number of monkeys: 16-9 = 7.

3. The method is the same as the number of double rooms in the question 1: (3 × 9-22)÷(3-2) = 5 (assuming that all 9 rooms are triple rooms).

Number of triple rooms: 9-5 = 4

4. The method is the same as the question 1: (3 10-3 × 80 )÷ (5-3) = 35.

Suppose all 80 pencils are 30 cents. )

Second, solve the problem.

1. Suppose 100 each of the teachers and students planted 5 trees. Then, a * * * planted 100 × 5 = 500 trees. There are more kinds than before.

500 to 200 = 300 trees. In addition, each student will plant 4 kinds of trees. Then, 300 ÷ 4 = 75 is the number of students. 100-75 = 25 is the number of teachers.

The formula is as follows: number of students: (100× 5-200) ÷ (5-1) = 75.

Number of teachers: 100-75 = 25

(the idea is still to give way and fill in the blanks. Question 1: The problem of chickens and rabbits in the same cage is the same. )

2. Solution: If there are X large oil bottles, there are (55-x) small oil bottles. According to the meaning of the question, the equation is as follows:

(55-x )÷ 2+4 x = 80 (multiply both sides by 2)

55-x+8 x = 160 (moving projects and merging similar projects)

7 x = 160 - 55

x = 105 ÷ 7

x = 15

The number of small oil bottles is 55- 15 = 40 (pieces)

Answer: large oil bottle 15, small oil bottle 40.

3. Solution: If X pieces are damaged, (250-x) pieces will be shipped intact. According to the meaning of the question, the equation is as follows:

(250-x )× 20- 100 x = 4400 (divide both sides by 20)

250-x-5 x = 220 (moving items and merging similar items)

250 - 220 = 6 x

30 = 6 x