0.25x7.8+7.8x0.74+0.78
=7.8x(0.25+0.74+0.1)
=7.8x1.09
=8.502
0.25×7.8+7.8×0.74+0.78
=0.25×7.8+7.8×0.74+7.8×0.1
=(0.25+0.74+0.1)×7.8
=1.09×7.8
=(1+0.1-0.01)×7.8
=7.8+0.1×7.8-0.01×7.8
=7.8+0.78-0.078
=8.58-0.078
=8.502
你好,这道题的简便算法如下:
0.25×7.8+7.8×0.74+0.078
=(0.25+0.74+0.01)×7.8
=1×7.8
=7.8
望采纳。