口算:865500-578900=95400+21560=258000-158000=125000+125000=3571000-2571000=2514980-2414980=
15.8-(6+÷12.5%)
10-÷×1
325×0.36+6.75×36
5.6×0.375+×5.4-0.375×0.9
求未知数(2分×2—4分)。= 3.5-0.7+8=16.4