Respostas

2014-02-18T14:50:13-03:00
A) X=>7xY=>7x5=> 35 
B)X+Y=27 =>X+5=27 =>X=27-5 => X=22
C)YX=10Y => 5X=10x5 => 5X=50 => X=50/5 => X=10
D)X/10=Y/60 =>X/10=5/60 => 60X=50 => X=50/60 => X=0,83
Acho que é isso