脱式计算，能简算的要简算
4.57+3.34÷0.21.68÷0.25÷0.4
2.5×0.7+7.5×0.70.125×0.32×0.25．
计算下面各题能简算的要简算
6.4÷0.8﹣1.5×41.9×2.34+1.9×7.661.25×6417÷[（1.2+0.5）×5]．
递等式计算（能巧则巧）
9.9×1.017.8÷1.25×8
0.25×（12﹣3.96÷18）0.24×15÷（3.25﹣2.35）
3.4×7.5+7.5×7.6﹣7.5．
递等式计算，能简算的要简算．
7.3×101﹣7.34.59÷4.5÷0.22.7﹣2.6×0.5
7.49×9.948÷0.8×1.2599×2.65+2.65
计算下面各题，能简算的要简算
6.4÷0.8﹣1.5×46.58×99+6.582.5×32 5.6×99．