49×1.4简便方法计算

2025-05-19 20:44:19
推荐回答(4个)
回答1:

49×1.4
=(50-1)×1.4
=50×1.4-1×1.4
=70-1.4
=68.6

回答2:

49x1.4
=(50-1)x1.4
=50x1.4-1.4
=70-1.4
=68.6

回答3:

(50一1)X1.4
=50X1.4一1X1.4
=70一1.4
=68.96

回答4:

=49X(1+0.4)
=49+19.6
=68.6