d = 80 / 10000
vmax = 0
For s = d To 80 - d Step d
b = Sqr(s)
c = b
a = (80 - s) / (4 * b)
v = a * b * c
If v > vmax Then
vmax = v
amax = a
bmax = b
cmax = c
End If
Next s
Selection.TypeText Text:=amax
Selection.TypeText Text:=","
Selection.TypeText Text:=bmax
Selection.TypeText Text:=","
Selection.TypeText Text:=cmax
Selection.TypeText Text:=","
Selection.TypeText Text:=vmax
Selection.TypeText Text:=","
Selection.TypeText Text:=(b * c + 2 * a * (b + c))