Solution: suppose this land has x hectares. In terms of meaning, x-(1/4x+5)-((3/4x-5) × 2/5-1) = 70, and the solution is x= 160, so this land * * has1.
2. I clearly read a science and technology book. In the first week, I read more than 1/8 of the total pages. Read the remaining 1/4 pages in the second week, leaving 155 pages. How many pages are there in this science book?
Solution: suppose this science and technology book has x pages. From the meaning of the title, x-(1/8x+10)-((7/8x-10) ×1/4-5) =155, x=240.
3. A factory burned 2/9 of a pile of coal on the first day, the remaining 2/7 on the second day, and burned 600 tons after making up the remaining 1/5 on the third day. How many tons of coal are there in the factory?
Solution: There used to be x tons of coal in the factory. According to the meaning of the question, x-2/9x-7/9x * 2/7+(x-2/9x-7/9x * 2/7) *1/5 = 600 and x=900, so the factory originally had 900 tons of coal.
A motorcade transports sand and cement to the construction site. Originally, there were 23 trucks carrying sand and 13 trucks carrying cement. According to the needs of the project, the number of trucks transporting cement can only account for 1/3 of the number of trucks transporting sand. How to allocate vehicles?
Solution: There are 13+23=36 trucks, and the number of trucks carrying cement can only account for 1/3 of trucks carrying sand, so there should be 36× 1/4=9 trucks carrying cement and 36-9=27 trucks carrying sand.
A vegetable base planted 600 mu of cucumber 120 mu of eggplant last year. According to the market demand, we want to make the planting area of eggplant reach 3/5 of that of cucumber this year. How much should the cucumber planting area be adjusted to grow eggplant?
Solution: Suppose that the area of planting cucumber in X mu should be adjusted to planting eggplant. X = 120+x=3/5(600-x) is derived from the meaning of the question.
Therefore, 150 mu of cucumber planting area should be adjusted to eggplant planting.
6. In a factory, male workers are nine-sevenths of female workers. After 50 new female workers were recruited, the male workers were 7/ 10. How many men and women workers are there in this factory?
Solution: Suppose there are X female workers in this factory. From the meaning of the question, 7/ 10(x+50)=7/9x, and x=450, so there are 450 female workers and 350 male workers in this factory.