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计算.(1)492425×(−5);(2)(−78)×12×(−117)(3)-7.8×(-8.1)×0×|-19.6|;(4)−|−0.25|×(−5)×4×(−125).(5)314−516−(−134)−356+1237−(−1247)(6)-|-32|-(-12)-72-(-5)

题目详情
计算.
(1)49
24
25
×(−5);
(2)(−
7
8
)×12×(−1
1
7
)
(3)-7.8×(-8.1)×0×|-19.6|;               
(4)−|−0.25|×(−5)×4×(−
1
25
).
(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
(6)-|-32|-(-12)-72-(-5)

49
24
25
×(−5);
(2)(−
7
8
)×12×(−1
1
7
)
(3)-7.8×(-8.1)×0×|-19.6|;               
(4)−|−0.25|×(−5)×4×(−
1
25
).
(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
(6)-|-32|-(-12)-72-(-5)
24
25
24242525
(−
7
8
)×12×(−1
1
7
)
(3)-7.8×(-8.1)×0×|-19.6|;               
(4)−|−0.25|×(−5)×4×(−
1
25
).
(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
(6)-|-32|-(-12)-72-(-5)
7
8
7788
1
7
1177

−|−0.25|×(−5)×4×(−
1
25
).
(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
(6)-|-32|-(-12)-72-(-5)
1
25
112525
3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
(6)-|-32|-(-12)-72-(-5)
1
4
1144
1
6
1166
3
4
3344
5
6
5566
3
7
3377
4
7
4477
▼优质解答
答案和解析
(1)49
24
25
×(−5)
=(50-
1
25
)×(-5)
=-50×5+
1
25
×5
=-250+
1
5

=-249
4
5


(2)(−
7
8
)×12×(−1
1
7
)
=
7
8
×
8
7
×12
=12;

(3)-7.8×(-8.1)×0×|-19.6|=0;               

(4)−|−0.25|×(−5)×4×(−
1
25
)
=-(
1
4
×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
49
24
25
242424252525×(−5)
=(50-
1
25
)×(-5)
=-50×5+
1
25
×5
=-250+
1
5

=-249
4
5


(2)(−
7
8
)×12×(−1
1
7
)
=
7
8
×
8
7
×12
=12;

(3)-7.8×(-8.1)×0×|-19.6|=0;               

(4)−|−0.25|×(−5)×4×(−
1
25
)
=-(
1
4
×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
1
25
111252525)×(-5)
=-50×5+
1
25
×5
=-250+
1
5

=-249
4
5


(2)(−
7
8
)×12×(−1
1
7
)
=
7
8
×
8
7
×12
=12;

(3)-7.8×(-8.1)×0×|-19.6|=0;               

(4)−|−0.25|×(−5)×4×(−
1
25
)
=-(
1
4
×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
1
25
111252525×5
=-250+
1
5

=-249
4
5


(2)(−
7
8
)×12×(−1
1
7
)
=
7
8
×
8
7
×12
=12;

(3)-7.8×(-8.1)×0×|-19.6|=0;               

(4)−|−0.25|×(−5)×4×(−
1
25
)
=-(
1
4
×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
1
5
111555
=-249
4
5


(2)(−
7
8
)×12×(−1
1
7
)
=
7
8
×
8
7
×12
=12;

(3)-7.8×(-8.1)×0×|-19.6|=0;               

(4)−|−0.25|×(−5)×4×(−
1
25
)
=-(
1
4
×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
4
5
444555;

(2)(−
7
8
)×12×(−1
1
7
)
=
7
8
×
8
7
×12
=12;

(3)-7.8×(-8.1)×0×|-19.6|=0;               

(4)−|−0.25|×(−5)×4×(−
1
25
)
=-(
1
4
×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
(−
7
8
777888)×12×(−1
1
7
111777)
=
7
8
×
8
7
×12
=12;

(3)-7.8×(-8.1)×0×|-19.6|=0;               

(4)−|−0.25|×(−5)×4×(−
1
25
)
=-(
1
4
×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
7
8
777888×
8
7
×12
=12;

(3)-7.8×(-8.1)×0×|-19.6|=0;               

(4)−|−0.25|×(−5)×4×(−
1
25
)
=-(
1
4
×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
8
7
888777×12
=12;

(3)-7.8×(-8.1)×0×|-19.6|=0;               

(4)−|−0.25|×(−5)×4×(−
1
25
)
=-(
1
4
×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
−|−0.25|×(−5)×4×(−
1
25
111252525)
=-(
1
4
×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
1
4
111444×4)×(5×
1
25

=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
1
25
111252525)
=-1×
1
5

=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
1
5
111555
=-
1
5


(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
1
5
111555;

(5)3
1
4
−5
1
6
−(−1
3
4
)−3
5
6
+12
3
7
−(−12
4
7
)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
3
1
4
111444−5
1
6
111666−(−1
3
4
333444)−3
5
6
555666+12
3
7
333777−(−12
4
7
444777)
=(3
1
4
+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
1
4
111444+1
3
4
)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
3
4
333444)-(5
1
6
+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
1
6
111666+3
5
6
)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
5
6
555666)+(12
3
7
+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
3
7
333777+12
4
7

=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.
4
7
444777)
=5-9+25
=21;

(6)-|-32|-(-12)-72-(-5)
=-32+12-72+5
=-104+17
=-87.