Respostas

2013-12-10T20:21:13-02:00
30x/100 = 21,3
30x = 21,3 . 100
30x = 2130
x = 2130/30
x = 213/3
x = 71
2013-12-10T20:55:40-02:00
30%-------------21,3
100%------------X
30X=100(21,3)
30x=2130
x=2130/30
x= 71