Formula in Excel

Question

Below is the data:

A          B          C
xxx        2          5
xxx        3          4
bbb        2          3
bbb        2.5        2
nnn        1.5        2
nnn        2          1

I want to subtract the amount in column B & C with the same description in column A

Answer 1

If you actually mean add columns B & C where column A is the same then what you want is a Pivot Table

Answer 2

If think what you are looking for is to use sumif(). For example if you use

=SUMIF(A1:A6,"nnn",B1:B6)

You will get a value of 3.5. If you then do

=SUMIF(A1:A6,"nnn",C1:C6)

You will get a value of 3. Take one away from another and you get 0.5. Does this suffice or are you looking for something more sophisticated?