问题
解答题
计算﹙用你喜欢的方法﹚
|
答案
(1)
÷5+5 18
×1 18
,1 5
=
×5 18
+1 5
×1 18
,1 5
=(
+5 18
)×1 18
,1 5
=
×1 3
,1 5
=
;1 15
(2)0.25×1.25×320,
=0.25×1.25×(40×8),
=(0.25×40)×(1.25×8),
=10×10,
=100;
(3)19.98×37-199.8×1.9+1998×0.82,
=1998×0.37-1998×0.19+1998×0.82,
=1998×(0.37-0.19+0.82),
=1998×1,
=1998;
(4)﹙
-1 6
+1 4
﹚×12,1 3
=
×12-1 6
×12+1 4
×12,1 3
=2-3+4,
=3;
(5)[1-﹙
+1 4
﹚]÷3 8
,3 4
=[1-
]÷5 8
,3 4
=
÷3 8
,3 4
=
;1 2
(6)[
+0÷﹙9 16
+1 7
﹚]×7 8
,4 3
=[
+0]×9 16
,4 3
=
×9 16
,4 3
=
;3 4
(7)20-[﹙
+1 2
﹚÷1 3
]×1.2,5 6
=20-[
÷5 6
]×1.2,5 6
=20-1×1.2,
=20-1.2,
=18.8;
(8)
×[15×﹙4 7
-1 3
﹚+3 10
],7 8
=
×[15×4 7
+1 30
],7 8
=
×[4 7
+1 2
],7 8
=
×4 7
,11 8
=
.11 14