Scazi din cantitatea initiala (85 l) a doua cantitate (60 l).
85-60=25 litri, acestia reprezentand cele 5 sticle in plus de vin. Impartim cantitatea la sticle, 25:5=5, deci o sticla are 5 litri.
Astfel, in primul transport magazinul a primit 85:5=17 sticle, in al doilea 60:5=12 sticle, in total primind 17+12=29 sticle.