Răspuns :
792-524=268-becuri rosii 403-268=135-becuri verzi 524-135=389-becuri galbene Verificare:268+135+389=792
b.r+b.v+b.g=792 becuri
br+bv=524b
bv.bg=403b
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br=?bv.=?bg.=>
bg.=702-524
bg.=178 becuri galbene
br=720-403
br=317 becuri rosii
bg=720-(317+178)
bg=720-495
bg.=225 becuri galbene
verificare
br+bv+bg=720 b
317+178+225=720 becuri
br+bv=524b
bv.bg=403b
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br=?bv.=?bg.=>
bg.=702-524
bg.=178 becuri galbene
br=720-403
br=317 becuri rosii
bg=720-(317+178)
bg=720-495
bg.=225 becuri galbene
verificare
br+bv+bg=720 b
317+178+225=720 becuri