Sub PickRandNumbers()
Dim rCell As Range, dNumber(1 To 120) As Double, iMax As Integer, i As Integer
For Each rCell In Range("A1:L10")
If rCell <> "" Then
iMax = iMax + 1
dNumber(iMax) = rCell
End If
Next
For i = 1 To 20
Range("N" & i) = dNumber(1 + Int(Rnd() * iMax))
Next
End Sub