用简便方法计算:42×(19⼀14-8⼀21) = = = =

2025-04-23 19:22:37
推荐回答(2个)
回答1:

=42x(19x3/42-8x2/42)=19x3-8x2=57-16=41

回答2:

=42×19/14-42×8/21
=3×19-2×8
=57-16
=41