1.2100-21×53+2255
2.(103-336÷21)×15
3.800-(2000-9600÷8)
4.40×48-(1472+328)÷5
5.(488+344)÷(202-194)
6.2940÷28+136×7
7.605×(500-494)-1898
8.(2886+6618)÷(400-346)
9.9125-(182+35×22)
10.(154-76)×(38+49)
11.3800-136×9-798
12.(104+246)×(98÷7)
13.918÷9×(108-99)
14.(8645+40×40)÷5
15.(2944+864)÷(113-79)
一元一次方程：
1.2(x-2)-3(4x-1)=9(1-x)
2.11x+64-2x=100-9x
3.15-(8-5x)=7x+(4-3x)
4.3(x-7)-2[9-4(2-x)]=22
5.3/2[2/3(1/4x-1)-2]-x=2
6.2(x-2)+2=x+1
7.0.4(x-0.2)+1.5=0.7x-0.38
8.30x-10(10-x)=100
9.4(x+2)=5(x-2)
10.120-4(x+5)=25
11.15x+863-65x=54
12.12.3(x-2)+1=x-(2x-1)
13.11x+64-2x=100-9x
14.14.59+x-25.31=0
15.x-48.32+78.51=80