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Math problem! ! ! ! ! It's due tomorrow ~! !
1. Xiaoming's comic books are six times that of Xiaohua. If two people buy two more books each, Xiaoming's comic books are four times as big as Xiaohua's. How many comic books do they each have?

Solution: Suppose Xiaohua has X books and Xiaoming has 6x books.

Judging from the meaning of the question:

6x+2=4(x+2)

Solution:

x=5

Then 6x = 5x6 = 30 (Ben)

After investigation, it conforms to the meaning of the question.

Xiaohua has 5 books, while Xiaoming has 30.

2. The distance between A and B is 420km, one is asphalt road and the other is dirt road. It takes eight hours for a car to drive from A to B. It is known that the speed of driving on asphalt road is 60 kilometers per hour, while the speed of driving on dirt road is 40 kilometers per hour. How long is the dirt road?

Solution: If the dirt road is x kilometers long and the asphalt road is (420-x) meters long.

Judging from the meaning of the question:

(420-x)÷60+x÷40=8

Solution:

x=60

After investigation, it conforms to the meaning of the question.

This dirt road is 60 kilometers long.

There are two piles of sand on the construction site. The first pile is 85 tons more than the second pile. After each pile used 30 tons of sand, the first pile was twice as large as the second pile. How many tons are there in each pile?

Solution: The first pile has X tons, and the second pile has (X-85) tons.

Judging from the meaning of the question:

x-30=2(x-85-30)

Solution:

x=200

After investigation, it conforms to the meaning of the question.

A: The first pile is 200 tons.

A group of young pioneers crossed the river by boat. If each ship takes 15 people, there are still 9 people left. If each ship takes 18 people, then only 1 ship remains. How many ships are there?

Solutions; Suppose there are X ships, then there are (15x+9) people.

Judging from the meaning of the question:

18(x- 1)= 15x+9

Solution:

x=9

After investigation, it conforms to the meaning of the question.

A: There are nine boats.

A typist typed a manuscript. On the first day, 30 pages were typed, and on the second day, 50 pages were typed, leaving 3/7 of the total pages. How many pages are there in this manuscript?

Solution: suppose: this manuscript has x pages.

Judging from the meaning of the question:

30+50=( 1-3/7)x

Solution:

x= 140

After investigation, it conforms to the meaning of the question.

A: This manuscript has 140 pages.

6. Xiaohua rides a bike and Tucki rides a motorcycle. They started from two places 80 kilometers apart at the same time. After meeting on the road, they walked back to each other. After five hours' departure, they are 205 kilometers apart. It is known that Xiaohua travels15km per hour. How many kilometers does Tucki travel per hour?

Solution: Suppose: Tucki travels x kilometers per hour.

Judging from the meaning of the question:

5( 15+x)=80+205

Solution:

x=42

After investigation, it conforms to the meaning of the question.

A: The speed in Tucki is 42 kilometers per hour.

7. The production team planted a batch of walnut trees and mangroves on the hillside. The number of walnut trees is twice that of mangroves, with 95 trees. It is known that there are 65,438+0,455 more walnut trees than mangroves. How many trees have been planted?

Solution: Suppose: if you plant X mangroves, you plant (2x+95) walnut trees.

Judging from the meaning of the question:

2x+95-x= 1455

Solution:

x= 1360

Then 2x+95 = 28 15 (tree)

Answer: If you plant 1360 mangroves, plant 28 15 walnuts.

When a bus leaves the station, there is a passenger on each seat, but there are no standing passengers. Passengers at the first stop 1/7 get off and get on 16. At the second stop, passenger 1/5 gets off and gets on at 5 o'clock. At this time, there is only one passenger in each seat.

Solution: suppose the number of passengers on the bus is X.

Judging from the meaning of the question:

( 16- 1/7x)+(5- 1/5x)= 9

Solution:

x=35

After investigation, it conforms to the meaning of the question.

A: The number of passengers on the bus is 35.