问题
解答题
计算. (1)(-24)×(
(2)(-7)×(-
(3)-2.1×5.4×(-
|
答案
(1)(-24)×(
-3 8
),5 6
=
×(-24)-3 8
×(-24),5 6
=-9+20,
=11;
(2)(-7)×(-
)×4 3
,5 14
=7×
×4 3
,5 14
=
;10 3
(3)-2.1×5.4×(-
),1 7
=2.1×5.4×
,1 7
=1.62.