Question

1 muncitor a sapat in 3 zile 1 sant lung de 12 mstiind ca in primele 2 zile a sapat 9 m iar in ultimele 2 zile 8mCiti m a sapat muncitorul?

Answer 1

$a + b + c = 12 \: m \\ a + b = 9 \: m \\ b + c = 8 \: m \\ \\ = > c = 12 - 9 = 3 \: m \\ = > a = 12 - 8 = 4 \: m \\ = > b = 9 - 4 = 5 \: m$