5^11 + 5^10
------------------- =
5^10 - 5^8
48,828,125 + 5^10
-------------------------- =
5^10 - 5^8
48,828,125 + 9,765,625
--------------------------------- =
5^10 - 5^8
48,828,125 + 9,765,625
----------------------------------- =
9,765,625 - 5^8
48,828,125 + 9,765,625
--------------------------------- =
9,765,625 - 390,625
58,593,750
------------------------------ =
9,765,625 - 390,625
58,593,750
------------------ =
9,375,000
answer: 6.25