formula to get average percentage?

Perhaps:

I3: =IF(COUNT(C3:H3),AVERAGE(C3:H3),"")
copied down

from that I think you can work out / adapt the above for the Row average ?

IF u want to exclude zeros so u can use an array formula like
=IFERROR(AVERAGE(IF((C3:H3<>"")*(C3:H3<>0),C3:H3)),"")
in I3, confirm w/ctrl+shift+enter and copy it down

No need for Array if using 2007 functions as implied by use of IFERROR - just use AVERAGEIF

=AVERAGEIF(C3:H3,"<>0",C3:H3)

whoops....

Might be a clever way of doing it that I can't think of right now, failing that a UDF could do it:

Function AverageAvg(rngAvg As Range) As Variant
Dim rngcell As Range, vSplit As Variant, dblX As Double, dblY As Double
For Each rngcell In rngAvg.Cells
    If InStr(rngcell.Formula, "/") Then
        vSplit = Split(Replace(rngcell.Formula, "=", ""), "/")
        dblX = dblX + vSplit(0)
        dblY = dblY + vSplit(1)
    End If
Next rngcell
If dblY Then AverageAvg = dblX / dblY Else AverageAvg = "n/a"
End Function

inserted into a module (ensure Macros enabled) and then called from a cell

I3: =AVERAGEAVG(C3:H3)
copied down