问题 解答题
[(+
1
7
)-(-
1
3
)-(+
1
5
)]÷(-
1
105
答案

[(+

1
7
)-(-
1
3
)-(+
1
5
)]÷(-
1
105

=(

1
7
+
1
3
-
1
5
)×(-105)

=

1
7
×(-105)+
1
3
×(-105)-
1
5
×(-105)

=-15-35+21

=-50+21

=-29.

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