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用简便方法计算:(1)−1.53×0.75+1.53×12+45×1.53(2)(213−312+1912)÷(−116).

题目详情
用简便方法计算:
(1)−1.53×0.75+1.53×
1
2
+
4
5
×1.53
(2)(2
1
3
−3
1
2
+1
9
12
)÷(−1
1
6
).
▼优质解答
答案和解析
(1)-1.53×0.75+1.53×
1
2
+
4
5
×1.53,
=1.53×(-0.75+0.5+0.8),
=1.53×(1.3-0.75),
=1.53×0.55,
=0.8415;
(2)(2
1
3
-3
1
2
+1
9
12
)÷(-1
1
6
),
=(
7
3
-
7
2
+
21
12
)×(-
6
7
),
=
7
3
×(-
6
7
)-
7
2
×(-
6
7
)+
21
12
×(-
6
7
),
=-2+3-
3
2

=3-3
1
2

=-
1
2