题目中间个括号内的1/23应该是1/53,否则不太简便哦


76x(1/23-1/53)+23x(1/53+1/76)-53x(1/23-1/76)
=76x1/23-76x1/53+23x1/53+23x1/76-53x1/23+53x1/76
=76/23-76/53+23/53+23/76-53/23+53/76
=(76/23-53/23)-(76/53-23/53)+(23/76+53/76)
=1-1+1
=1