问题
解答题
|
答案
(1)57.26-(5.26-1.5),
=57.26-5.26+1.5,
=52+1.5,
=53.5;
(2)64×1.25×2.5,
=8×8×1.25×2.5,
=(8×1.25)×(8×2.5),
=10×20,
=200;
(3)(
+4 9
)÷2 15
,2 15
=(
+4 9
)×2 15
,15 2
=
×4 9
+15 2
×2 15
,15 2
=
+1,10 3
=4
;1 3
(4)4.8×3.9+6.1×4
,4 5
=(3.9+6.1)×4.8,
=10×4.8,
=48;
(5)12×(
+1 6
-1 4
),1 3
=12×
+12×1 6
-12×1 4
,1 3
=2+3-4,
=1;
(6)(
+1 4
)÷4 5
+7 3
,7 10
=(
+1 4
)×4 5
+3 7
,7 10
=
×21 20
+3 7
,7 10
=
+9 20
,14 20
=1
;3 20
(7)34.5×9.23-34.5+1.77×34.5,
=34.5×(9.23-1+1.77),
=34.5×10,
=345;
(8)2-
÷6 13
-9 26
,2 3
=2-
×6 13
-26 9
,2 3
=2-
-4 3
,2 3
=2-(
+4 3
),2 3
=0.