Răspuns:
8 viori............5 chitare..........2000 ron
2 viori............6 chitare...........1260 ron I×4
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8 viori............24 chitare..........5040 ron
8 viori............5 chitare...........2000 ron
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/ 19c=3040=>c=3040:19=>c=160 ron costa o chitara
8v+5×160=2000
8v=2000-800
v=1200:8
v=150 ron costa o vioara