Question

Corina a cumparat 12 kg de fructe:mere ,portocale si banane. Merele si portocalele cantaresc 7kg,iar portocalele si bananele 8 kg. Cate kg de fiecare fel a cumparat Corina ?

Answer 1

m + p + b = 12 kg
m + p       =   7 kg
       p + b =   8 kg
--------------------------------
7 kg + b = 12 kg
b = 12 - 7
b = 5 kg

m + 8 kg = 12 kg
m = 12 - 8
m = 4 kg

p + 5 + 4 = 12
p + 9 = 12 kg
p = 12 - 9
p = 3 kg