Respostas

2014-05-14T21:09:54-03:00
13,7999... = 

13 + 79 - 7
          90

13 + 72 =
        90

90 * 13 + 72 = 1242
       90              90
2014-05-14T21:13:19-03:00
13,79..
x=13,79..
10x=137,9..
100x=1379,99...

100x=1379,9..
-
10x=137,9..
=90x= 1242
=1242/90
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