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(2013•黄冈模拟)计算,前两题用简便方法计算.

来源:学生作业帮 编辑:作业帮 分类:综合作业 时间:2024/05/23 18:27:40
(2013•黄冈模拟)计算,前两题用简便方法计算.
①(
2
7
(1)(
2
7+
1
5)×7×5
=
2
7×35+
1
5×35,
=10+7,
=17;

(2)
3
13×
4
5+
10
13×
4
5-
4
5
=(
3
13+
10
13−1)×
4
5,
=0×
4
5,
=0;

(3)(9+92+93)×0.01
=819×0.01,
=8.19;

(4)13.5×[1.5×(1.07+1.93)]
=13.5×[1.5×3],
=13.5×4.5,
=60.75;

(5)
1
12+
11
12×(
5
2-
1
3)
=
1
12+
11
12×
13
6,
=
1
12+
143
72,
=
149
72;

(6)(333+667)÷[63×(
4
7-
4
9)]
=1000÷[63×
8
63],
=1000÷8,
=125;