脱式计算，能简算的要简算．
（7.6﹣1+80%）÷（1﹣30%）     75%×0.375+1.625×﹣0.75         24﹣4.62﹣5.38
1.25×2.5×32                   [﹣（25%+）]÷10%              ÷[（﹣）×]．