五分之二除以括号负二又五分之二括号减21分之八乘以括号负一又四分之三括号负零点二五除以二乘以二分之

2024-12-26 03:02:14
推荐回答(1个)
回答1:

2/5÷(-2又2/5)-8/21×(-1又3/4)-0.75
=2/5÷(-12/5)-8/21×(-7/4)-0.75
=-1/6+2/3-3/4
=1/2-3/4
=-1/4