18.9*178.178+0.49-17.8*189.18 简算

来源:学生作业学帮网 编辑:学帮网 时间:2024/05/31 00:09:48

18.9*178.178+0.49-17.8*189.18
简算

=18.9*178.178+0.49-17.8*(189+0.18)
=18.9(178.178-178)+0.49-17.8*0.18
=18.9*0.178+0.49-17.8*0.18
=0.178*(18.9-18)+0.49
=0.178*0.9+0.49
=0.6502

18.9*178.178+0.49-17.8*189.18
=3367.5642+0.49-3367.404
=3368.0542-3367.404
=0.6502