puieti de stejar = PS
fag = F
mesteacan = M
PS + F + M = 810
PS + M = 422
PS + F = 644
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PS = ?, F = ?, M = ?
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644 + M = 810
M = 810 - 644
M = 166
PS + M = 422
PS + 166 = 422
PS = 422 - 166
PS = 256
PS + F = 644
256 + F = 644
F = 644 - 256
F = 388
Sper ca te-am ajutat :)