Hi,

Am Fri, 16 Nov 2012 08:17:18 +0000 schrieb murtaza7210:

Sales Cash, Sales Credit then column B should accept a positive value
0,
else if the selection in column A is Purchase Cash, Purchase Credit then
column B should accept a negative value <0

select your range in column B = data validation = custom:
=IF(LEFT(A1,5)="Sales",B10,B1<0)


Regards
Claus Busch
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Win XP PRof SP2 / Vista Ultimate SP2
Office 2003 SP2 /2007 Ultimate SP2