critic this please

[NJM]

I've just wrote this small program that calculates the length of a rafter
for you(I'm a carpenter), but I didn't write it "properly".  I can't seem to
wrap my head around using classes.  Does anyone have any input.


 import Tkinter

def fig5():
  a = float(Tkinter.Entry.get(feet))
  b = float(Tkinter.Entry.get(inch))
  Tkinter.Entry.delete(answer, 0, 20)
  Tkinter.Entry.insert(answer, 0, (b/12 + a)*13)

def fig6():
  a = float(Tkinter.Entry.get(feet))
  b = float(Tkinter.Entry.get(inch))
  Tkinter.Entry.delete(answer, 0, 20)
  Tkinter.Entry.insert(answer, 0, (b/12 + a)*13.42)
def fig7():
  a = float(Tkinter.Entry.get(feet))
  b = float(Tkinter.Entry.get(inch))
  Tkinter.Entry.delete(answer, 0, 20)
  Tkinter.Entry.insert(answer, 0, (b/12 + a)*13.89)

def fig8():
  a = float(Tkinter.Entry.get(feet))
  b = float(Tkinter.Entry.get(inch))
  Tkinter.Entry.delete(answer, 0, 20)
  Tkinter.Entry.insert(answer, 0, (b/12 + a)*14.42)

def fig9():
  a = float(Tkinter.Entry.get(feet))
  b = float(Tkinter.Entry.get(inch))
  Tkinter.Entry.delete(answer, 0, 20)
  Tkinter.Entry.insert(answer, 0, (b/12 + a)*15)

def fig10():
  a = float(Tkinter.Entry.get(feet))
  b = float(Tkinter.Entry.get(inch))
  Tkinter.Entry.delete(answer, 0, 20)
  Tkinter.Entry.insert(answer, 0, (b/12 + a)*15.62)
def fig11():
  a = float(Tkinter.Entry.get(feet))
  b = float(Tkinter.Entry.get(inch))
  Tkinter.Entry.delete(answer, 0, 20)
  Tkinter.Entry.insert(answer, 0, (b/12 + a)*16.28)
def fig12():
  a = float(Tkinter.Entry.get(feet))
  b = float(Tkinter.Entry.get(inch))
  Tkinter.Entry.delete(answer, 0, 20)
  Tkinter.Entry.insert(answer, 0, (b/12 + a)*16.97)


root=Tkinter.Tk(className="/Rafter Lengths")
frame=Tkinter.Frame(root, relief=Tkinter.RIDGE, borderwidth=2)
frame.pack()
label=Tkinter.Label(frame, text="This is a program that will calculate the
rafter lengths for you")
label.pack()

frame2=Tkinter.Frame(root, borderwidth=0)
frame2.pack()

button=Tkinter.Button(frame2, text="'5-12'", command=fig5)
button.pack(side=Tkinter.LEFT)
button2=Tkinter.Button(frame2, text="'6-12'", command=fig6)
button2.pack(side=Tkinter.LEFT)
button3=Tkinter.Button(frame2, text="'7-12'", command=fig7)
button3.pack(side=Tkinter.LEFT)
button4=Tkinter.Button(frame2, text="'8-12'", command=fig8)
button4.pack(side=Tkinter.LEFT)
button5=Tkinter.Button(frame2, text="'9-12'", command=fig9)
button5.pack(side=Tkinter.LEFT)
button6=Tkinter.Button(frame2, text="'10-12'", command=fig10)
button6.pack(side=Tkinter.LEFT)
button7=Tkinter.Button(frame2, text="'11-12'", command=fig11)
button7.pack(side=Tkinter.LEFT)
button8=Tkinter.Button(frame2, text="'12-12'", command=fig12)
button8.pack(side=Tkinter.LEFT)
button9=Tkinter.Button(frame2, text="Quit", command=root.quit)
button9.pack(side=Tkinter.LEFT)

frame3=Tkinter.Frame(root, borderwidth=5)
frame3.pack()

labe=Tkinter.Label(frame3, text="Rafter Run to be calculated")
labe.pack(side=Tkinter.LEFT)

space=Tkinter.Label(frame3, width=5)
space.pack(side=Tkinter.LEFT)

label2=Tkinter.Label(frame3, text="Feet")
label2.pack(side=Tkinter.LEFT)
feet=Tkinter.Entry(frame3, width=5)
feet.pack(side=Tkinter.LEFT)

label3=Tkinter.Label(frame3, text="Inches", width=5)
label3.pack(side=Tkinter.LEFT)
inch=Tkinter.Entry(frame3, width=5)
inch.pack(side=Tkinter.LEFT)

frame4=Tkinter.Frame(root, relief=Tkinter.RIDGE, borderwidth=2)
frame4.pack()

label4=Tkinter.Label(frame4, text="Rafter Length in Inches")
label4.pack(side=Tkinter.LEFT)
answer=Tkinter.Entry(frame4)
answer.pack(side=Tkinter.LEFT)

frame5=Tkinter.Frame(root)
frame5.pack()

label5=Tkinter.Label(frame5, text="This length does not allow for \n the
thickness of the ridge.")
label5.pack()

root.mainloop()