在等差数列｛an｝中，若a3+a4+a5+a6+a7=25，则a2+a8=____________．

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问题在等差数列｛a_n｝中，若a₃+a₄+a₅+a₆+a₇=25，则a₂+a₈=____________．

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答案10

解析由等差数列性质得，a₃+a₄+a₅+a₆+a₇=5a₅=25，解得a₅=5，所以a₂+a₈=2a₅=10．

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中学数学

教师公开招聘

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在等差数列｛an｝中，若a3+a4+a5+a6+a7=25，则a2+a8=____________．

中学数学

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