Count Sale Days Between Sold Articles

In table A i have the purchase date of all the articles bought with their corresponding quantities.

Table A:
Purches DateArticleQuantity12/12/2008Radio2012/12/2008Binocular6012/12/2008Fan3112/12/2008Iron5012/12/2008Sun Glass15012/12/2008Tv612/12/2008Head Phone3712/12/20082G Card12


In table B i have the sold dates of all the articles with their corresponding quantities.

Table B:
Sold On ArticleQuantity15/12/2008Iron115/12/20082G Card115/12/2008Radio216/12/2008Tv116/12/2008Iron217/01/2008Head Phone317/12/2008Iron117/12/20082G Card122/12/2008Radio127/12/2008Fan1

An finally table C is a result chart which shows the days between the purchase and the selling dates of the articles.

Table C:
Article Sale After purches date 12/12/2008 Days ?Sale RepeatRadioBinocularFanIronSun GlassTvHead Phone2G CardAfter Every ? Days3163453After Every ? Days1145After Every ? Days5After Every ? DaysAfter Every ? DaysAfter Every ? DaysAfter Every ? DaysAfter Every ? DaysAfter Every ? DaysAfter Every ? DaysAfter Every ? Days