Respostas

2014-06-26T13:22:58-03:00
Xicara = a      pires = b
a + b = 7
a = b +2

b+2 + b =7
2b= 7-2
b =5/2
b = 2,50

a+b=7
a + 2,50 = 7
a = 4,50
2 5 2