我会巧算．
1.2×0.4+1.3×0.4   （1.25+0.36）×0.2    7.2×0.3+28×0.03    0.25×0.56×0.4
8×（2.5+0.125）     0.25×0.56×0.4     32.8+5.6+7.2        75.2﹣66.9﹣5.2．