解方程：
| x+3.2=10.83 | x÷13=20 | 9x-36=5x |
| 2.5×3-2x=0.5 | 4（2-x）=1 | x÷1.7-0.8=6． |
| 63÷7= | 580+200= | 60×7= | 350+500= | 35+8= |
| 270-70= | 420×3= | 30÷6= | 700-120= | 240+80= |
| 34-18= | 88÷9= | 90×4= | 93-63= | 8×0= |
| 15×6= |  + = | 1- = |  - = |  + = |
| x+3.2=10.83 | x÷13=20 | 9x-36=5x |
| 2.5×3-2x=0.5 | 4（2-x）=1 | x÷1.7-0.8=6． |
| 63÷7= | 580+200= | 60×7= | 350+500= | 35+8= |
| 270-70= | 420×3= | 30÷6= | 700-120= | 240+80= |
| 34-18= | 88÷9= | 90×4= | 93-63= | 8×0= |
| 15×6= | += | 1-= | -= | += |
（a不为0）的分数单位是________，它含有________个这样的单位，当a是________时，它的分数的值为最小的质数．
，a与b的比是________，b比a多________．