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    The number of integer solutions for the syetem of inequalities 数学公式 about x is just 6，then the range of value for real number a is
    （integersolutions整数解；syetem of inequalities不等式组；the range of value取值范围）


    1. A.
      -2.5＜a≤-2
    2. B.
      -2.5≤a≤-2
    3. C.
      -5＜a≤-4
    4. D.
      -5≤a≤-4
    A
    分析：根据不等式的性质求出不等式的解集，根据不等式的解集找出不等式组的解集，根据已知得到-5＜2a≤-4，求出即可．
    解答：，
    解①得：x≥2a，
    解②得：x＜2，
    ∴不等式组的解集是2a≤x＜2，
    ∵不等式组的整数解有6个，
    ∴-5＜2a≤-4，
    ∴-2.5＜a≤-2．
    故选A．
    点评：本题考查了解一元一次不等式（组）的应用，能求出关于a的不等式-5＜2a≤-4是解此题的关键．
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