有一分数序列:1/2,2/3,3/5,5/8,8/13,---,求出这个数列的前20项之和。

Private Sub form_Click()
 Dim fz%, fm%, f%, i%, s!
 fz = 1
 fm = 2
 s = 0
    For i = 1 To 20
    s = s + fz / fm
    f = fz + fm
    fz = fm
    fm = f
    Next i
Print s;
End Sub