口算.(近似值符号的是估算题)
| 0.105×100= | 1993+1994= | 603×39≈ | 4950÷51= | 112-102= |
| 16×0.25= | 19÷9-10÷9= | 8π≈ | 2.63+3.7= | |
| 1- | 7×8×( | 1- |
解下列方程
| x-6=7.6 | 3+x=5.4 | 5x=1.5 | x÷5=15. |
| 0.105×100= | 1993+1994= | 603×39≈ | 4950÷51= | 112-102= |
| 16×0.25= | 19÷9-10÷9= | 8π≈ | 2.63+3.7= | |
| 1- | 7×8×( | 1- |
| x-6=7.6 | 3+x=5.4 | 5x=1.5 | x÷5=15. |