用竖式计算下面各题.(第2小题要验算)(1)350×24 (2)1189÷4.
用递等式计算.(1)(2)(3).
+ + ++ ﹣ ﹣++ ﹣﹣ 1﹣++﹣.
计算:= 1﹣= = = == = 1﹣= = =
+=﹣==改正:
用推算计算(1)+=(2)﹣=