Respostas

2014-02-13T21:34:25-02:00
PREÇO/R$           PORCENTAGEM/%
   965,00                           100
       x                                   72 (100 - 28)   multiplicando cruzado, temos:
100x = 965, 00 . 72    isolando x, temos:

x = 965,00  .  72/100
x = 69.480/100
x = R$ 694,80
1 5 1
2014-02-13T21:36:19-02:00
965 ⇒ 100
x ⇒28
100x = 27020
x=27020/100
270.20-965= 694.80