5-3×7⼀9等于2×7⼀9等于4⼀9对?

2025-05-20 00:05:44
推荐回答(1个)
回答(1):

5-3×7/9=2×7/9=4/9
错误。违反了先乘除后加减的定理。
5-3×7/9
=5-7/3
=5-2-1/3
=2又3分之2