18.9x178.178+0.49-17.8x189.189如何简算?
问题描述:
18.9x178.178+0.49-17.8x189.189如何简算?
答
18.9x178.178+0.49-17.8x189.189
=18.9*178*1.001+0.49-17.8*189*1.001
=18.9*17.8*10*1.001+0.49-17.8*18.9*10*1.001
=0.49