在D4单元格输入以下公式
=IF(B4="小红","6天",IF(B4="小蓝","20天",IF(B4="小黑","13天","")))
详见附图
D4输入=IF(B4="小红","6天",IF(B4="小蓝","20天",IF(B4="小黑","13天","")))回车。
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