(20-5-3)x+45=300
12x +45=300
12x =255
x=255/ 12
A: In the next few days, at least 255/ 12 pieces will be processed every day on average.
Quantity to be completed in the next few days+45 pieces processed three days before construction = 300 pieces in total.
Solution: Suppose a candidate must answer the X question correctly to make the score not lower than 130.
10x-4(20-x)>= 130
10x-80+4x & gt; = 130
14x & gt; = 130+80
14x & gt; =2 10
x & gt= 15
A: Candidates must answer 15 correctly or above to get a score of not less than 130.
X's correct answer score+incorrect answer score (20-X) > = 130.
Solution: Each type of work has X employees, and each type of work has (150-x) employees.
x & gt=2( 150-x)
X>= 300-2 times
x+2x & gt; =300
X & gt= 100
1200x 100+800x50
= 120000+40000
= 160000 (yuan)
A: Each recruit for Type B 100, and each recruit for Type A is 50. The monthly salary is at least 160000 yuan.
Count the number of people first, then the price.