a+b+c=176 pagini
b=c+28
a=b-c a=c+28-c
Cate pagini are al 3 volum? /-----------/
c+28-c+c+28+c=176 pagini
2c=176-56
2c=120
al treilea volum are 60 pagini
Cat are al 2 volum? /----------/ +28
b=60+28=88 pagini
Cat are primul volum? /-----------/+28 - /------------/ = 28
a=88-60=28 pagini
verific
28+88+60=176 pagini