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体育用品仓库里有许多足球、排球和篮球,某班</SPAN>50</SPAN>名同学来仓库拿球,规定每个人至少拿</SPAN>1</SPAN>个球,至多拿</SPAN>2</SPAN>个球,问至少有几名同学所拿的球种类是一致的?</SPAN></STRONG>

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