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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×
+
×1.53
(2)(2
−3
+1
)÷(−1
).
(1)−1.53×0.75+1.53×
1 |
2 |
4 |
5 |
(2)(2
1 |
3 |
1 |
2 |
9 |
12 |
1 |
6 |
▼优质解答
答案和解析
(1)-1.53×0.75+1.53×
+
×1.53,
=1.53×(-0.75+0.5+0.8),
=1.53×(1.3-0.75),
=1.53×0.55,
=0.8415;
(2)(2
-3
+1
)÷(-1
),
=(
-
+
)×(-
),
=
×(-
)-
×(-
)+
×(-
),
=-2+3-
,
=3-3
,
=-
.
1 |
2 |
4 |
5 |
=1.53×(-0.75+0.5+0.8),
=1.53×(1.3-0.75),
=1.53×0.55,
=0.8415;
(2)(2
1 |
3 |
1 |
2 |
9 |
12 |
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 |
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