Adding to a formula

[JDSOuth49]

I have this formula that I have been working with:
=IF(WEEKDAY(B5)<=5,IF(S15>8,8,S15),0)

NOW: I need to add cell P15 (+P15) to the formula above.
I have tried: =IF(WEEKDAY(B5)<=5,IF(S15>8,8,S15),0)+(P15), this works fine if there is a value in cell (P15), but not when there is not a value in cell (P15) and this is returned ###.

Can any one help me with this?

 

[akmatz]

Try this:
=IF(WEEKDAY(B5)<=5,IF(S15>8,8,S15),0)+if(P15<>"",P15,0)"

 

[JDSOuth49]

Works great, Thank you...