I have three cells A1 A2 and A3
In one or two of them there will be a value and in the third there will be a
"not available" value. Iwant a fourth cell which will read the maximum of the
two values, but should also take into account NA cell.
(max)
A1 A2 A3 A4
23 NA NA 23
24 36 NA 36
12 NA NA 12
14 24 12 24