(80- 18)×(5+x)=80×5
62×(5+x)=400
3 10+62x=400
62x=90
x=45/3 1
A: It will take two more days to process.
2. Solution: Suppose there are x million science and technology books, then there are 2 million literature and art books.
x+2x=2.7
3x=2.7
x=0.9
2x=2×0.9= 1.8
A: There are 9,000 books on science and technology and 65,438+8,000 books on literature and art..
3. Solution: Assume that X pieces are produced every day on average.
6×64+2x=580
384+2x=580
2x= 196
x=98
A: On average, 98 units are produced every day.
4. Solution: X yuan buys basketball and 3 yuan buys football.
x+3x= 1 140
4x= 1 140
x=285
3x=3×285=855
A: It costs 285 yuan to buy basketball and 855 yuan to buy football.
5. Solution: Set the car B to travel at the speed of X kilometers per hour.
6×(49+x)=540
49+x =90
x =4 1
A: The speed of the second train is 4 1 km.
6. Solution: If Xiaohua is X years old this year and Grandpa is 8x years old this year.
8x-x=56
7x=56
x=8
8x=8×8=64
A: Xiaohua is 8 years old and Grandpa is 64 years old.