a+b+c+d=120 sa se afle a,b ,c si d stiind ca a+5,b-5, c:5, dx5 numere egale
daca a+5,b-5, c:5, dx5 sunt numere egale => a+5 = b-5 = c:5 = dx5 = 120/4 = 30 (pt ca a + b + c + d = 120) =>
a+5 = 30 => a = 30-5=25
b-5 = 30 => b = 30+5=35
c:5 = 30 => c = 30x5 = 150
dx5 = 30 => d = 30/5 = 6