Respostas

2014-02-19T19:13:29-03:00
após 4 % 

28 ------------------- 100 %
  x -------------------    4 %

100x = 28 . 4
100x = 112
x = 112 / 100
x = 1,12

1,12 + 28 = 29,12

após 6 %

28 -------------- 100 %
  x --------------    6 %

100x = 28 . 6
100x = 168
x = 168 / 100
x = 1,68

1,68 + 28 = 29,6
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