Ultimul cumparator a gasit in cos 10 oua,al treilea a gasit 2*10=20 oua (din care a luat doar jum),al doilea a gasit 8/8 din care a cumparat 3/8 si au ramas cele 20 oua(adica 5/8) ,daca 5/8=20 atunci 3/8= 12oua a cumparat deci erau in cos canda venit 20+12=32 oua ;primul gaseste 5/5 ,cumpara 1/5 si raman 4/5=32 , adica 1/5=8(a cumparat). Si deci in cos erau 32+8=40 oua