计算：
800﹣240= 65÷8= 45÷9= 50÷7= 1081+24=
（12+78）×4= 500×4= 210×2+80= 3600÷9 0×9+1=
计算下面各题，能简算的要简算．
⑴0.9+1.08+0.92+0.1
⑵32.54﹣10.46﹣4.54
⑶18.73+3.85﹣2.73
⑷45.6﹣（83.7﹣78.8）
用竖式计算并验算．
⑴5.84+26.36=
⑵10.25﹣9.68=
⑶20﹣12.39=
⑷15.8+16.28=
口算．
| ⑴0.9+0.4= |
⑵9﹣0.7= |
⑶0.36+0.54= |
⑷1﹣0.26= |
| ⑸3.6+0.4= |
⑹1.29﹣0.29= |
⑺0.74+0.26= |
⑻0.57﹣0.5= |
| ⑼2.8+1.12= |
⑽6.2+1.8= |
⑾2.8﹣2.3= |
⑿1.3﹣0.6= |
算一算．
| ⑴ |
⑵ |
⑶ |
⑷ |
 ﹣ = |
 ﹣ = |
  = |
 + = |
| ⑸ |
⑹ |
⑺ |
⑻ |
1﹣ = |
 ﹣= |
 + = |
 += |
| ⑴42×23+15 |
⑵28×35﹣80 |
| ⑶780﹣38×12 |
⑷（55+43）×14 |
| ⑸（87+67）÷2 |
⑹54÷3×16 |