- 7 / 5 - 12 / 30 = - 7 / 5 - 2 / 5 = - 9 / 5 = - 1 intreg si 4 / 5 = - 1,8
12 / 30 = ( 12 : 6 ) / ( 30 : 6 ) = 2 / 5
==> am simplificat cu 6