Ebook + telefon + tableta = 900 ron
Ebook= telefon + 50 - > telefon = ebook - 50
Ebook = tableta - 35 -> tableta = ebook + 35
Ebook + ebook - 50 + ebook + 35 = 900 ron
3 x ebook - 50+ 35 =900 ron
3 x ebook = 915 ron
Ebook = 305
Tableta = 305 + 35
Telefon = 305 - 50