Simple Math

[Guest]

How do I perform the calculation for inventory items that
when items are sold it subtracts from stock level balance.
Example: If I have 10 radios and I sell three How do I
show 7 for the new balance

 

[Jerry W. Lewis]

=10-3
or if the balance is in A1 and the amount sold is in B1, then
=A1-B1

Jerry