Assume that you have 3 approvers in a work flow and need to update the item status based on these approvers individual task outcome
1. Approver1_Status
2. Approver2_Status
3. Approver3_Status
You are updating a calculated column Status_Calc based on approvers status.
And the scenario is if any approver rejects the request the item status need to set as Rejected and if the final approver approves, set item status as Approved
The [Status_Calc] value will be
=IF([Approver3_Status]="Approved","Approved",IF([Approver3_Status]="Rejected","Rejected",IF([Approver2_Status]="Rejected","Rejected",IF([Approver1_Status]="Rejected","Rejected"))))
Hope this helps...