Respostas

2014-02-01T18:13:34-02:00
100---------900
42-----------x
100x=900*42
x=37800/100
x=378
2014-02-01T18:22:07-02:00
Basta calcularmos 42% de 900

0,42 . 900 = 378 alunos.

R= 378 rapazes