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28×(1/251+1/223)-223×(1/28-1/251)+251×(1/28-1/223)简便计算,

题目详情
28×(1/251+1/223)-223×(1/28-1/251)+251×(1/28-1/223)
简便计算,
▼优质解答
答案和解析
28×(1/251+1/223)-223×(1/28-1/251)+251×(1/28-1/223)
=28×1/251+28×1/223)-223×1/28+223×1/251+251×1/28-251×1/223
=(28/251+223/251)+(28/223-251/223)+(251/28-223/28)
=1-1+1
=1