You could create a formula that sets the value of totals into variables and compute the value you are looking for.  If these numbers are from a group footer, in the footer you could deploy a formula that has some if statements in it like 'if type="Cash" then Cash:=(the summary value)' Later on you could have another if like 'if Cash<>0 and AR <> 0 then Cash+AR'  I know either/both Cash or AR might be 0 (times are rough) so you might set them initiall to some bogus number and compare to that, but this should give you the middle column.  It won't be pretty, but it should work.

use another if to only execute the calculation if the first type is 'Cash' or 'AR', otherwise print "" which will display nothing.