blank cells

[datadude1959]

I need to calculate times that someone arrived somewhere and what time
they had a test done. So far, I have figured these functions out,
however, I have arrival time in say A2, testing time in A4, with the
calculated time showing up in A8. If either A2 or A4 is blank, I need
N/A to show up in A8????

Thanks

 

[flydecoder]

Try this
=if(or(A2="",A4=""),"N/A",<your existing formula>)

 

[datadude1959]

Sorry it took so long to say, Thank You