用简便方法计算.①2.5×0.125×28×8 ②87×99 ③48×30.
6.4×2.5+2×3.4+25% 15.7×7.7+1.57×22+1.5712.56﹣(+2.56+) ×﹣×2010× 3.65÷〔0.1÷(2.1﹣2.09)〕
①②③④99×88+88×77+77×66+66×55.
(78.6﹣0.786×25十75%×21.4)÷15×1997.
324×11.25+65.8×112.5 8888008×125 0.525÷13 125÷4×85.2
① ②0.25×0.09×8③1÷[÷(1﹣)] ④×18+×11.