问题
解答题
直接写出计算结果: 125×25×32= 4.9×5
29×
(0.12×40+13×0.4)-
|
答案
(1)125×25×32,
=125×25×(4×8),
=(125×8)×(25×4),
=1000×100,
=100000;
(2)4.9×5
+4.9+31 2
×4.9,1 2
=4.9×(5
+1+31 2
),1 2
=4.9×10,
=49;
(3)29×
,17 28
=(28+1)×
,17 28
=
×28+1×17 28
,17 28
=17+
,17 28
=17
;17 28
(4)(0.12×40+13×0.4)-
-25,3 4
=(12+13)×0.4-
-25,3 4
=10-0.75-25,
=-15.75.