问题
解答题
|
答案
(1)9.63-7.52-2.49+0.43,
=(9.63+0.43)-(7.52+2.49),
=10.06-10.01,
=0.05;
(2)2000-1998+1996-1994+…-6+4-2,
=++…+(8-6)+(4-2),
=2×500,
=1000;
(3)
×(0.875×12.4+1+4.4×1 2
)×7 8
-4 3
,1 4
=
×(2 3
×12.4+1+4.4×7 8
)-7 8
,1 4
=
×[(12.4+4.4)×2 3
+1]-7 8
,1 4
=
×[16.8×2 3
+1]-7 8
,1 4
=
×[14.7+1]-2 3
,1 4
=
×15.7-2 3
,1 4
=
×(15+2 3
)-7 10
,1 4
=10+
-7 15
,1 4
=10
;13 60
(4)[1-(
+1 12+ 1 2
)×21 10
]÷1 2
,11 25
=[1-(
+1 25 2
)×21 10
]÷1 2
,11 25
=[1-(
+2 25
)×21 10
]÷1 2
,11 25
=[1-
×9 50
]÷5 2
,11 25
=[1-
]×9 20
,25 11
=
×11 20
,25 11
=
.5 4