You've hi-jacked Grandma B's post, but try this in C2 of Sheet C:

=IF(ISNA(VLOOKUP(A2,'Sheet A'!A$2:C$1000,3,0)),0,
VLOOKUP(A2,'Sheet A'!A$2:C$1000,3,0)) +
IF(ISNA(VLOOKUP(A2,'Sheet B'!A$2:C$1500,3,0)),0,
VLOOKUP(A2,'Sheet B'!A$2:C$1500,3,0))

This is all one formula - I've split it to avoid awkward line breaks.
I've assumed you have a table of 1000 items in Sheet A and 1500 items
in Sheet B, so adjust these values to suit your data, then copy the
formula down.

Hope this helps.

Pete

vlook fomula wrote:

Sheet A has
Col A: Inventory code
Col B: Description
Col C: Quantity

Sheet B has
Col A: Inventory code
Col B: Description
Col C: Quantity ( both sheets have same data but inventory code may be
different)

Sheet C required
Required: total quantity of sheet A and sheet B in Col. C of sheet C

Kindly help me to create a logical formula / vlook formula

Example

Sheet A

Col A Col B Col C
Inventory code Description Quantity
10001 pencil 25
10002 pen 50
10003 rubber 75

Sheet B
Col A Col B Col C
Inventory code Description Quantity
10001 pencil 25
10002 pen 50
10004 Duster 15


Sheet C
Col A Col B Col C
Inventory code Description Total Qty of sheet A & Sheet B
10001 pencil ? ( total required with the help of vlook formula)
10002 pen ?
10003 rubber ?
10004 Duster ?

Zafar