问题 解答题
脱式计算(能简算的要用简便方法计算):
①80÷(1-84%)②5-5×
2
5
+
3
5
③0.25×32×12.5%
7
9
÷
11
5
+
2
9
×
5
11
答案

①80÷(1-84%),

=80÷0.16,

=500;

②5-5×

2
5
+
3
5

=5-2+

3
5

=3

3
5

③0.25×32×12.5%,

=0.25×4×8×0.125,

=(0.25×4)×(8×0.125),

=1×1,

=1;

7
9
÷
11
5
+
2
9
×
5
11

=

7
9
×
5
11
+
2
9
×
5
11

=(

7
9
+
2
9
)×
5
11

=1×

5
11

=

5
11

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