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计算:(1)−87.21+531921−12.79+46221(2)3-2×(-5)2;(3)318-135(精确到0.01);(4)66×(12−13×511);(5)−22÷23×(1−13)2;(6)23×(−214)−3−338.

题目详情
计算:
(1)−87.21+53
19
21
−12.79+46
2
21

(2)3-2×(-5)2
(3)
318
-
1
3
5
(精确到0.01);
(4)66×(
1
2
1
3
×
5
11
);
(5)2
2
3
×(1−
1
3
)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8

−87.21+53
19
21
−12.79+46
2
21

(2)3-2×(-5)2
(3)
318
-
1
3
5
(精确到0.01);
(4)66×(
1
2
1
3
×
5
11
);
(5)2
2
3
×(1−
1
3
)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8
19
21
19192121
2
21
222121
2
318
-
1
3
5
(精确到0.01);
(4)66×(
1
2
1
3
×
5
11
);
(5)2
2
3
×(1−
1
3
)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8
318
318318
1
3
5
(精确到0.01);
(4)66×(
1
2
1
3
×
5
11
);
(5)2
2
3
×(1−
1
3
)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8
1
3
5
1
3
5
1
3
5
3
5
3355
66×(
1
2
1
3
×
5
11
);
(5)2
2
3
×(1−
1
3
)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8
1
2
1122
1
3
1133
5
11
551111
2
2
3
×(1−
1
3
)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8
2
2
3
×(1−
1
3
)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8
2
2
3
×(1−
1
3
)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8
2
3
×(1−
1
3
)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8
2
3
2233
1
3
1133)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8
)2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8
2;
(6)
2
3
×(−
2
1
4
)−
3−3
3
8

2
3
×(−
2
1
4
)−
3−3
3
8
2
3
2233
2
1
4
2
1
4
2
1
4
1
4
1144
3−3
3
8
3−3
3
8
3−3
3
8
3
8
3388
▼优质解答
答案和解析
(1)原式=(-87.21-12.79)+(531921+46221)=-100+100=0;(2)原式=3-2×25=3-50=-47;(3)原式≈2.62074-1.2649≈1.36;(4)原式=66×(12-533)=66×12-66×533=33-10=23;(5)原式=-4×32×49=-83;(6)原...