一又4/5=9/51又四分之一=5/49/5×1.25+5/4×1.2-5/4=9/5x5/4+5/4x6/5-5/4=5/4x(9/5+6/5-1)=5/4x10/5=5/2=2.5谢谢，请采纳
一又4/5=9/51又四分之一=5/49/5×1.25+5/4×1.2-5/4=9/5x5/4+5/4x6/5-5/4=5/4x(9/5+6/5-1)=5/4x10/5=5/2=2.5
题目错了
