Răspuns:
c = 5
l = 3
Explicație pas cu pas:
4 l _____ 7 c _____ 47 RON
7 l _____ 5 c _____ 46 RON
......................................................................................................
20 l _____ 35 c _____ 235 RON
49 l _____ 35 c _____ 322 RON
......................................................................................................
49 l - 20 l = 322 RON - 235 RON
29 l = 87 RON
l = 87 ÷ 29
l = 3 RON
......................................................................................................
12 + 7 c = 47
7 c = 47 - 12
7 c = 35
c = 35 ÷ 7
c = 5 RON
Verificare:
4 · 3 + 7 · 5 = 47
12 + 35 = 47
47 = 47 (A)