Make a plan and read it in x days.
20x= 18(x+ 1)
20x- 18x= 18
2x= 18
x=9
Pages: 20×9= 180 pages
2. The young pioneers of the school visited the Science and Technology Museum and rented several buses. If each bus takes 48 people, the buses organized by the school are just full. If each bus takes 42 people, then two groups of cars are needed. How many buses have you rented? How many young pioneers are going to visit?
Suppose x buses are rented.
48x=42(x+2)
48x-42x=42×2
6x=42×2
x= 14
Number: 48× 14=672
3. A batch of coal is shipped out from the power plant. If you use 40,000 tons every day, it will be used up as planned. If you use 43,000 tons a day, it will be used up nine days in advance. How many days do you plan to use? How many tons is this batch of coal?
Suppose this batch of coal is planned to run out in x days.
4x=4.3(x-9)
4.3x-4x=4.3×9
0.3x=4.3×9
x= 129
Total coal quantity: 4× 129=5 16 tons.
4. The China Scarlet Letter Society will deliver a batch of daily necessities to poor areas. If each car is loaded with 5000 kilograms, then the goods are just finished. If each car is loaded with 6500 kilograms, then six cars can be sent less. How many tons are there in this batch of daily necessities?
Suppose this batch of daily necessities has x tons.
x÷5000=x÷6500+6
13x= 10x+6×65000
3x=6×65000
x=2×65000
x= 130000
Xiao pang leaves home for school at 7: 30 every morning. If he walks 70 meters per minute, he is just ready to go to school. If he walks 60 meters per minute, he will be five minutes late. If Xiao Pang walks 70 meters per minute, can he get to school at 8 o'clock?
If Xiao Pang walks 70 meters per minute, it takes X minutes.
70x=60(x+5)
10x=60×5
x=30
If Xiao Pang walks 70 meters per minute, he can get to school at 8 o'clock.
6. A class of students went boating. If each boat has four students, then the planned boat is just full; If each boat carries six students, you can rent three fewer boats. How many ships did you originally plan to rent? How many students are there in this class?
Suppose the original plan was to rent x boats.
4x=6(x-3)
6x-4x= 18
x=9
There are 4×9=36 students in this class.