问题 解答题
怎样简便怎样算:
10
13
÷2
19
22
-1
2
5
×
11
13
÷7+
1
5
×
22
63
4
5
-
1
6
+
5
12
)×60
1994×19931994-1993×19941994(20.2×0.4+7.88)÷4.2.
答案

(1)

10
13
÷2
19
22
-1
2
5
×
11
13
÷7+
1
5
×
22
63

=

10
13
×
22
63
-
7
5
×
11
13
×
1
7
+
1
5
×
22
63

=

10
13
×
22
63
-
1
5
×
11
13
+
1
5
×
22
63

=(

10
13
+
1
5
)×
22
63
-
11
65

=

63
65
×
22
63
-
11
65

=

22
65
-
11
65

=

11
65

(2)(

4
5
-
1
6
+
5
12
)×60,

=

4
5
×60-
1
6
×60+
5
12
×60,

=48-10+25,

=38+25,

=63;

(3)1994×19931994-1993×19941994,

=1994×19931994-1993×1994×10001,

=1994×19931994-1994×19931993,

=1994×(19931994-19931993),

=1994×1,

=1994;

(4)(20.2×0.4+7.88)÷4.2,

=(20.2×0.4+7.88)÷4.2,

=(8.08+7.88)÷4.2,

=15.96÷4.2,

=3.8.

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