问题 解答题
用简便方法计算:
24×
2
7
×
5
72
×21                  17×
11
23
+17÷
23
12
答案

①24×

2
7
×
5
72
×21

=(24×

5
72
)×(
2
7
×21)

=

5
3
×6

=10;

②17×

11
23
+17÷
23
12

=17×

11
23
+17×
12
23

=17×(

11
23
+
12
23

=17×1

=17.

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