Practical questions (30 19:1:19) Mechanical processing needs lubrication to reduce friction. An enterprise needs to process 90kg lubricating oil for a large-scale mechanical equipment, and the reuse rate of lubricating oil is 60%. According to this calculation, the actual oil consumption of processing a large-scale mechanical equipment is 36kg. In order to build a conservation oriented society and reduce oil consumption, a workshop of the enterprise organized personnel to tackle key problems to reduce the actual oil consumption, It not only reduces the lubricating oil consumption, but also improves the reuse rate of lubricating oil. It is found that on the basis of technological innovation, the reuse rate of lubricating oil consumption will increase by 1.6% for every 1kg reduction in lubricating oil consumption. In this way, the actual oil consumption of processing a large mechanical equipment will decrease to 12kg, How many kilos of lubricating oil is used for processing a large mechanical equipment? What is the reuse rate of lubricating oil?

Practical questions (30 19:1:19) Mechanical processing needs lubrication to reduce friction. An enterprise needs to process 90kg lubricating oil for a large-scale mechanical equipment, and the reuse rate of lubricating oil is 60%. According to this calculation, the actual oil consumption of processing a large-scale mechanical equipment is 36kg. In order to build a conservation oriented society and reduce oil consumption, a workshop of the enterprise organized personnel to tackle key problems to reduce the actual oil consumption, It not only reduces the lubricating oil consumption, but also improves the reuse rate of lubricating oil. It is found that on the basis of technological innovation, the reuse rate of lubricating oil consumption will increase by 1.6% for every 1kg reduction in lubricating oil consumption. In this way, the actual oil consumption of processing a large mechanical equipment will decrease to 12kg, How many kilos of lubricating oil is used for processing a large mechanical equipment? What is the reuse rate of lubricating oil?

First, the oil consumption is reduced by XKG, so the oil consumption is 90-xkg
Then according to the principle of "every 1 kg reduction in lubricating oil consumption, the reuse rate of lubricating oil consumption will increase by 1.6%"
The reusability of the obtained oil is (60 + 1.6x)%
(90-X)*[1-(60+1.6X)%]=12
(X-90)*(X-25)=750
=> X^2-115X+1500=0 ,
We get x = 100 or x = 15, obviously x = 15,
Therefore, the oil consumption is 75 kg, and the oil reuse rate is 84%